diff --git a/build/check.py b/build/check.py
index f8552a8ce..1f6799ddb 100755
--- a/build/check.py
+++ b/build/check.py
@@ -283,7 +283,6 @@ def check_tests(args):
       [closure_base_js]))
   files.add(os.path.join(base, 'demo', 'common', 'asset.js'))
   files.add(os.path.join(base, 'demo', 'common', 'assets.js'))
-  files.add(os.path.join(base, 'demo', 'common', 'message_ids.js'))
 
   localizations = compiler.GenerateLocalizations(None)
   localizations.generate(args.force)
diff --git a/demo/asset_card.js b/demo/asset_card.js
index dbe71173d..4544f8257 100644
--- a/demo/asset_card.js
+++ b/demo/asset_card.js
@@ -8,7 +8,6 @@ goog.provide('shakaDemo.AssetCard');
 
 goog.require('goog.asserts');
 goog.require('shakaAssets');
-goog.require('shakaDemo.MessageIds');
 goog.require('shakaDemo.Tooltips');
 goog.requireType('ShakaDemoAssetInfo');
 
@@ -134,7 +133,7 @@ shakaDemo.AssetCard = class {
 
   /**
    * @param {string} icon
-   * @param {!shakaDemo.MessageIds} title
+   * @param {string} title
    * @private
    */
   addFeatureIcon_(icon, title) {
@@ -190,18 +189,17 @@ shakaDemo.AssetCard = class {
 
   /**
    * Modify an asset to make it clear that it is unsupported.
-   * @param {!shakaDemo.MessageIds} unsupportedReason
+   * @param {string} unsupportedReason
    */
   markAsUnsupported(unsupportedReason) {
     this.card_.classList.add('asset-card-unsupported');
-    this.makeUnsupportedButton_(
-        shakaDemo.MessageIds.UNSUPPORTED, unsupportedReason);
+    this.makeUnsupportedButton_('Not Available', unsupportedReason);
   }
 
   /**
    * Make a button that represents the lack of a working button.
-   * @param {?shakaDemo.MessageIds} buttonName
-   * @param {!shakaDemo.MessageIds} unsupportedReason
+   * @param {?string} buttonName
+   * @param {string} unsupportedReason
    * @return {!Element}
    * @private
    */
@@ -306,16 +304,15 @@ shakaDemo.AssetCard = class {
       return;
     }
 
-    this.makeYesNoDialogue_(parentDiv,
-        shakaDemo.MessageIds.DELETE_STORED_PROMPT, async () => {
-          deleteButton.disabled = true;
-          await this.asset_.unstoreCallback();
-        });
+    this.makeYesNoDialogue_(parentDiv, 'Delete the offline copy?', async () => {
+      deleteButton.disabled = true;
+      await this.asset_.unstoreCallback();
+    });
   }
 
   /**
    * @param {!Element} parentDiv
-   * @param {!shakaDemo.MessageIds} text
+   * @param {string} text
    * @param {function():Promise} callback
    * @private
    */
@@ -330,14 +327,14 @@ shakaDemo.AssetCard = class {
 
     const textElement = document.createElement('h2');
     textElement.classList.add('mdl-typography--title');
-    textElement.textContent = shakaDemoMain.getLocalizedString(text);
+    textElement.textContent = text;
     dialog.appendChild(textElement);
 
     const buttonsDiv = document.createElement('div');
     dialog.appendChild(buttonsDiv);
-    const makeButton = (textId, fn) => {
+    const makeButton = (text, fn) => {
       const button = document.createElement('button');
-      button.textContent = shakaDemoMain.getLocalizedString(textId);
+      button.textContent = text;
       button.classList.add('mdl-button');
       button.classList.add('mdl-button--colored');
       button.classList.add('mdl-js-button');
@@ -348,12 +345,12 @@ shakaDemo.AssetCard = class {
       buttonsDiv.appendChild(button);
       button.blur();
     };
-    makeButton(shakaDemo.MessageIds.PROMPT_YES, async () => {
+    makeButton('Yes', async () => {
       dialog.close();
       await callback();
       this.remakeButtons();
     });
-    makeButton(shakaDemo.MessageIds.PROMPT_NO, () => {
+    makeButton('No', () => {
       dialog.close();
     });
 
@@ -385,9 +382,9 @@ shakaDemo.AssetCard = class {
   /**
    * Adds a button to the bottom of the card that will call |onClick| when
    * clicked. For example, a play or delete button.
-   * @param {?shakaDemo.MessageIds} name
+   * @param {?string} name
    * @param {function()} onclick
-   * @param {shakaDemo.MessageIds=} yesNoDialogText
+   * @param {string=} yesNoDialogText
    * @return {!HTMLButtonElement}
    */
   addButton(name, onclick, yesNoDialogText) {
@@ -397,7 +394,7 @@ shakaDemo.AssetCard = class {
     button.classList.add('mdl-button--colored');
     button.classList.add('mdl-js-button');
     button.classList.add('mdl-js-ripple-effect');
-    button.textContent = name ? shakaDemoMain.getLocalizedString(name) : '';
+    button.textContent = name || '';
     button.addEventListener('click', () => {
       if (!button.hasAttribute('disabled')) {
         if (yesNoDialogText) {
diff --git a/demo/cast_receiver/index.html b/demo/cast_receiver/index.html
index e7454d2ac..7fda5f9cc 100644
--- a/demo/cast_receiver/index.html
+++ b/demo/cast_receiver/index.html
@@ -52,7 +52,6 @@ UNCOMPILED_JS = [
   // This file contains goog.require calls for all exported library classes.
   '../../shaka-player.uncompiled.js',
   // These are the individual parts of the receiver app.
-  '../common/message_ids.js',
   '../common/asset.js',
   '../common/assets.js',
   'receiver_app.js',
diff --git a/demo/close_button.js b/demo/close_button.js
index 570ff38d5..041fa5ea5 100644
--- a/demo/close_button.js
+++ b/demo/close_button.js
@@ -41,9 +41,6 @@ shakaDemo.CloseButton = class extends shaka.ui.Element {
             });
           });
     }
-
-    // TODO: Make sure that the screenreader description of this control is
-    // localized!
   }
 };
 
diff --git a/demo/common/asset.js b/demo/common/asset.js
index e17a4cfb0..fb9e36a4c 100644
--- a/demo/common/asset.js
+++ b/demo/common/asset.js
@@ -12,8 +12,6 @@
 
 goog.provide('ShakaDemoAssetInfo');
 
-goog.require('shakaDemo.MessageIds');
-
 
 /**
  * An object that contains information about an asset.
@@ -115,9 +113,9 @@ const ShakaDemoAssetInfo = class {
   }
 
   /**
-   * A sort comparator for comparing two message Ids, ignoring case.
-   * @param {shakaDemo.MessageIds} a
-   * @param {shakaDemo.MessageIds} b
+   * A sort comparator for comparing two messages, ignoring case.
+   * @param {string} a
+   * @param {string} b
    * @return {number}
    * @private
    */
diff --git a/demo/common/assets.js b/demo/common/assets.js
index 2a4ed40df..0b8ee93d5 100644
--- a/demo/common/assets.js
+++ b/demo/common/assets.js
@@ -11,7 +11,6 @@
  */
 
 goog.require('ShakaDemoAssetInfo');
-goog.require('shakaDemo.MessageIds');
 
 goog.provide('shakaAssets');
 
@@ -24,34 +23,34 @@ goog.provide('shakaAssets');
 const shakaAssets = {};
 
 
-/** @enum {shakaDemo.MessageIds} */
+/** @enum {string} */
 shakaAssets.Source = {
-  CUSTOM: shakaDemo.MessageIds.CUSTOM,
-  SHAKA: shakaDemo.MessageIds.SHAKA,
-  AXINOM: shakaDemo.MessageIds.AXINOM,
-  UNIFIED_STREAMING: shakaDemo.MessageIds.UNIFIED_STREAMING,
-  DASH_IF: shakaDemo.MessageIds.DASH_IF,
-  BITCODIN: shakaDemo.MessageIds.BITCODIN,
-  METACDN: shakaDemo.MessageIds.METACDN,
-  NIMBLE_STREAMER: shakaDemo.MessageIds.NIMBLE_STREAMER,
-  AZURE_MEDIA_SERVICES: shakaDemo.MessageIds.AZURE_MEDIA_SERVICES,
-  GPAC: shakaDemo.MessageIds.GPAC,
-  UPLYNK: shakaDemo.MessageIds.UPLYNK,
-  APPLE: shakaDemo.MessageIds.APPLE,
-  IRT: shakaDemo.MessageIds.IRT,
-  MICROSOFT: shakaDemo.MessageIds.MICROSOFT,
-  VNOVA: shakaDemo.MessageIds.VNOVA,
+  CUSTOM: 'Custom',
+  SHAKA: 'Shaka',
+  AXINOM: 'Axinom',
+  UNIFIED_STREAMING: 'Unified Streaming',
+  DASH_IF: 'DASH-IF',
+  BITCODIN: 'Bitcodin',
+  METACDN: 'MetaCDN',
+  NIMBLE_STREAMER: 'Nimble Streamer',
+  AZURE_MEDIA_SERVICES: 'Azure Media Services',
+  GPAC: 'GPAC',
+  UPLYNK: 'Verizon Digital Media Services',
+  APPLE: 'Apple',
+  IRT: 'IRT',
+  MICROSOFT: 'Microsoft',
+  VNOVA: 'V-Nova',
 };
 
 
-/** @enum {shakaDemo.MessageIds} */
+/** @enum {string} */
 shakaAssets.KeySystem = {
-  CLEAR_KEY: shakaDemo.MessageIds.CLEAR_KEY,
-  FAIRPLAY: shakaDemo.MessageIds.FAIRPLAY,
-  PLAYREADY: shakaDemo.MessageIds.PLAYREADY,
-  WIDEVINE: shakaDemo.MessageIds.WIDEVINE,
-  AES128: shakaDemo.MessageIds.AES128,
-  CLEAR: shakaDemo.MessageIds.CLEAR,
+  CLEAR_KEY: 'Clear Key DRM',
+  FAIRPLAY: 'Fairplay DRM',
+  PLAYREADY: 'PlayReady DRM',
+  WIDEVINE: 'Widevine DRM',
+  AES128: 'AES-128 protection',
+  CLEAR: 'No DRM protection',
 };
 
 
@@ -95,65 +94,65 @@ shakaAssets.identifierForKeySystem = (keySystem) => {
 };
 
 
-/** @enum {shakaDemo.MessageIds} */
+/** @enum {string} */
 shakaAssets.Feature = {
   // Set if the asset has a special trick mode track, for rewinding effects.
-  TRICK_MODE: shakaDemo.MessageIds.TRICK_MODE,
-  XLINK: shakaDemo.MessageIds.XLINK,
+  TRICK_MODE: 'Special trick mode track',
+  XLINK: 'XLink',
 
   // Set if the asset has any subtitle tracks.
-  SUBTITLES: shakaDemo.MessageIds.SUBTITLES,
+  SUBTITLES: 'Subtitles',
   // Set if the asset has any closed caption tracks.
-  CAPTIONS: shakaDemo.MessageIds.CAPTIONS,
+  CAPTIONS: 'Captions',
   // Set if the asset has multiple audio languages.
-  MULTIPLE_LANGUAGES: shakaDemo.MessageIds.MULTIPLE_LANGUAGES,
+  MULTIPLE_LANGUAGES: 'Multiple languages',
   // Set if the asset is audio-only.
-  AUDIO_ONLY: shakaDemo.MessageIds.AUDIO_ONLY,
+  AUDIO_ONLY: 'Audio only',
   // Set if the asset can be stored offline.
-  OFFLINE: shakaDemo.MessageIds.OFFLINE,
+  OFFLINE: 'Downloadable',
   // A synthetic property used in the "all content" tab. Should not be given to
   // assets.
-  STORED: shakaDemo.MessageIds.STORED,
+  STORED: 'Downloaded',
   // Set if the asset has ads. Autoset by calling setAdTagUri() on an asset.
   // Does not need to be set manually.
-  ADS: shakaDemo.MessageIds.ADS,
+  ADS: 'Ads',
 
   // Set if the asset is a livestream.
-  LIVE: shakaDemo.MessageIds.LIVE,
+  LIVE: 'Live',
   // A synthetic property used if the asset is VOD (not-livestream).
-  VOD: shakaDemo.MessageIds.VOD,
+  VOD: 'VOD',
   // Set if the asset has at least one WebM stream.
-  WEBM: shakaDemo.MessageIds.WEBM,
+  WEBM: 'WebM',
   // Set if the asset has at least one mp4 stream.
-  MP4: shakaDemo.MessageIds.MP4,
+  MP4: 'MP4',
   // Set if the asset has at least one MPEG-2 TS stream.
-  MP2TS: shakaDemo.MessageIds.MP2TS,
+  MP2TS: 'MPEG-2 TS',
   // Set if the asset has at least one containerless stream (AAC, etc).
-  CONTAINERLESS: shakaDemo.MessageIds.CONTAINERLESS,
+  CONTAINERLESS: 'Containerless',
 
   // Set if the asset has at least one stream that is at least 720p.
-  HIGH_DEFINITION: shakaDemo.MessageIds.HIGH_DEFINITION,
+  HIGH_DEFINITION: 'High definition',
   // Set if the asset has at least one stream that is at least 4k.
-  ULTRA_HIGH_DEFINITION: shakaDemo.MessageIds.ULTRA_HIGH_DEFINITION,
+  ULTRA_HIGH_DEFINITION: 'Ultra-high definition',
 
   // Set if the asset has at least one stream that is surround sound.
-  SURROUND: shakaDemo.MessageIds.SURROUND,
+  SURROUND: 'Surround sound',
 
   // Set if the asset is a MPEG-DASH manifest.
-  DASH: shakaDemo.MessageIds.DASH,
+  DASH: 'DASH',
   // Set if the asset is an HLS manifest.
-  HLS: shakaDemo.MessageIds.HLS,
+  HLS: 'HLS',
   // Set if the asset is an MSS manifest.
-  MSS: shakaDemo.MessageIds.MSS,
+  MSS: 'MSS',
 
   // Set if the asset has at least one image stream.
-  THUMBNAILS: shakaDemo.MessageIds.THUMBNAILS,
+  THUMBNAILS: 'Thumbnails',
 
   // Set if the asset has LCEVC.
-  LCEVC: shakaDemo.MessageIds.LCEVC,
+  LCEVC: 'LCEVC',
 
   // Set if the asset has Low Latency mode.
-  LOW_LATENCY_STREAM: shakaDemo.MessageIds.LOW_LATENCY_STREAM,
+  LOW_LATENCY_STREAM: 'Low Latency Streams',
 };
 
 
diff --git a/demo/common/message_ids.js b/demo/common/message_ids.js
deleted file mode 100644
index 316ee28c9..000000000
--- a/demo/common/message_ids.js
+++ /dev/null
@@ -1,311 +0,0 @@
-/*! @license
- * Shaka Player
- * Copyright 2016 Google LLC
- * SPDX-License-Identifier: Apache-2.0
- */
-
-goog.provide('shakaDemo.MessageIds');
-
-/* eslint-disable max-len */
-/** @enum {string} */
-shakaDemo.MessageIds = {
-  /* Features. */
-  ADS: 'DEMO_ADS',
-  AUDIO_ONLY: 'DEMO_AUDIO_ONLY',
-  CAPTIONS: 'DEMO_CAPTIONS',
-  CONTAINERLESS: 'DEMO_CONTAINERLESS',
-  DASH: 'DEMO_DASH',
-  HIGH_DEFINITION: 'DEMO_HIGH_DEFINITION',
-  HLS: 'DEMO_HLS',
-  LCEVC: 'DEMO_LCEVC',
-  LIVE: 'DEMO_LIVE',
-  MP2TS: 'DEMO_MP2TS',
-  MP4: 'DEMO_MP4',
-  MSS: 'DEMO_MSS',
-  MULTIPLE_LANGUAGES: 'DEMO_MULTIPLE_LANGUAGES',
-  OFFLINE: 'DEMO_OFFLINE',
-  STORED: 'DEMO_STORED',
-  SUBTITLES: 'DEMO_SUBTITLES',
-  SURROUND: 'DEMO_SURROUND',
-  THUMBNAILS: 'DEMO_THUMBNAILS',
-  TRICK_MODE: 'DEMO_TRICK_MODE',
-  ULTRA_HIGH_DEFINITION: 'DEMO_ULTRA_HIGH_DEFINITION',
-  VOD: 'DEMO_VOD',
-  WEBM: 'DEMO_WEBM',
-  XLINK: 'DEMO_XLINK',
-  LOW_LATENCY_STREAM: 'DEMO_LOW_LATENCY_STREAM',
-  /* Key systems. */
-  AES128: 'DEMO_AES128',
-  CLEAR: 'DEMO_CLEAR',
-  CLEAR_KEY: 'DEMO_CLEAR_KEY',
-  FAIRPLAY: 'DEMO_FAIRPLAY',
-  PLAYREADY: 'DEMO_PLAYREADY',
-  WIDEVINE: 'DEMO_WIDEVINE',
-  /* Sources. */
-  APPLE: 'DEMO_APPLE',
-  AXINOM: 'DEMO_AXINOM',
-  AZURE_MEDIA_SERVICES: 'DEMO_AZURE_MEDIA_SERVICES',
-  BITCODIN: 'DEMO_BITCODIN',
-  CUSTOM: 'DEMO_CUSTOM',
-  DASH_IF: 'DEMO_DASH_IF',
-  GPAC: 'DEMO_GPAC',
-  IRT: 'DEMO_IRT',
-  METACDN: 'DEMO_METACDN',
-  MICROSOFT: 'DEMO_MICROSOFT',
-  NIMBLE_STREAMER: 'DEMO_NIMBLE_STREAMER',
-  SHAKA: 'DEMO_SHAKA',
-  UNIFIED_STREAMING: 'DEMO_UNIFIED_STREAMING',
-  UPLYNK: 'DEMO_UPLYNK',
-  /* HTML. */
-  ALL_CONTENT: 'DEMO_ALL_CONTENT',
-  CDN_HEADER: 'DEMO_CDN_HEADER',
-  COMPILED_DEBUG: 'DEMO_COMPILED_DEBUG',
-  COMPILED_RELEASE: 'DEMO_COMPILED_RELEASE',
-  CONFIG: 'DEMO_CONFIG',
-  CUSTOM_CONTENT: 'DEMO_CUSTOM_CONTENT',
-  DEMO_MODE_HEADER: 'DEMO_DEMO_MODE_HEADER',
-  DOCUMENTATION: 'DEMO_DOCUMENTATION',
-  HOME: 'DEMO_HOME',
-  JSDELIVR: 'DEMO_JSDELIVR',
-  LIBRARIES: 'DEMO_LIBRARIES',
-  LICENSE: 'DEMO_LICENSE',
-  NPM: 'DEMO_NPM',
-  PROJECT_LINKS_HEADER: 'DEMO_PROJECT_LINKS_HEADER',
-  REPORT_BUG: 'DEMO_REPORT_BUG',
-  SOURCE: 'DEMO_SOURCE',
-  SUPPORT: 'DEMO_SUPPORT',
-  UNCOMPILED: 'DEMO_UNCOMPILED',
-  /* Common. */
-  FAILURE_MISC: 'DEMO_FAILURE_MISC',
-  FAILURE_NO_BROWSER_SUPPORT: 'DEMO_FAILURE_NO_BROWSER_SUPPORT',
-  PLAY: 'DEMO_PLAY',
-  PROMPT_NO: 'DEMO_PROMPT_NO',
-  PROMPT_YES: 'DEMO_PROMPT_YES',
-  UNSUPPORTED_DISABLED: 'DEMO_UNSUPPORTED_DISABLED',
-  UNSUPPORTED_NO_DASH_SUPPORT: 'DEMO_UNSUPPORTED_NO_DASH_SUPPORT',
-  UNSUPPORTED_NO_DOWNLOAD: 'DEMO_UNSUPPORTED_NO_DOWNLOAD',
-  UNSUPPORTED_NO_FORMAT_SUPPORT: 'DEMO_UNSUPPORTED_NO_FORMAT_SUPPORT',
-  UNSUPPORTED_NO_HLS_SUPPORT: 'DEMO_UNSUPPORTED_NO_HLS_SUPPORT',
-  UNSUPPORTED_NO_OFFLINE: 'DEMO_UNSUPPORTED_NO_OFFLINE',
-  UNSUPPORTED_NO_KEY_SUPPORT: 'DEMO_UNSUPPORTED_NO_KEY_SUPPORT',
-  UNSUPPORTED_NO_LICENSE_SUPPORT: 'DEMO_UNSUPPORTED_NO_LICENSE_SUPPORT',
-  UNSUPPORTED_NO_MSS_SUPPORT: 'DEMO_UNSUPPORTED_NO_MSS_SUPPORT',
-  /* Visualizer. */
-  VISUALIZER_AUTO_SCREENSHOT_TOGGLE: 'DEMO_VISUALIZER_AUTO_SCREENSHOT_TOGGLE',
-  VISUALIZER_BUTTON: 'DEMO_VISUALIZER_BUTTON',
-  VISUALIZER_SCREENSHOT_BUTTON: 'DEMO_VISUALIZER_SCREENSHOT_BUTTON',
-  /* Asset card. */
-  DELETE_STORED_PROMPT: 'DEMO_DELETE_STORED_PROMPT',
-  UNSUPPORTED: 'DEMO_UNSUPPORTED',
-  /* Front panel. */
-  FRONT_INTRO_DISMISS: 'DEMO_FRONT_INTRO_DISMISS',
-  FRONT_INTRO_ONE: 'DEMO_FRONT_INTRO_ONE',
-  FRONT_INTRO_TWO: 'DEMO_FRONT_INTRO_TWO',
-  /* Custom panel. */
-  AD_TAG_URL: 'DEMO_AD_TAG_URL',
-  ADS_TAB: 'DEMO_ADS_TAB',
-  IMA_ASSET_KEY: 'DEMO_IMA_ASSET_KEY',
-  IMA_CONTENT_SRC_ID: 'DEMO_IMA_CONTENT_SRC_ID',
-  IMA_MANIFEST_TYPE: 'DEMO_IMA_MANIFEST_TYPE',
-  IMA_VIDEO_ID: 'DEMO_IMA_VIDEO_ID',
-  CANCEL_BUTTON: 'DEMO_CANCEL_BUTTON',
-  CUSTOM_INTRO_ONE: 'DEMO_CUSTOM_INTRO_ONE',
-  CUSTOM_INTRO_TWO: 'DEMO_CUSTOM_INTRO_TWO',
-  CUSTOM_INTRO_THREE: 'DEMO_CUSTOM_INTRO_THREE',
-  DELETE_CUSTOM: 'DEMO_DELETE_CUSTOM',
-  DELETE_CUSTOM_PROMPT: 'DEMO_DELETE_CUSTOM_PROMPT',
-  DRM_SYSTEM: 'DEMO_DRM_SYSTEM',
-  DRM_TAB: 'DEMO_DRM_TAB',
-  EDIT_CUSTOM: 'DEMO_EDIT_CUSTOM',
-  HLS_FULL_MIME_TYPE: 'DEMO_HLS_FULL_MIME_TYPE',
-  HLS_TAB: 'DEMO_HLS_TAB',
-  HEADERS_TAB: 'DEMO_HEADERS_TAB',
-  ICON_URL: 'DEMO_ICON_URL',
-  LICENSE_CERTIFICATE_URL: 'DEMO_LICENSE_CERTIFICATE_URL',
-  LICENSE_HEADER_NAME: 'DEMO_LICENSE_HEADER_NAME',
-  LICENSE_HEADER_TITLE: 'DEMO_LICENSE_HEADER_TITLE',
-  LICENSE_HEADER_VALUE: 'DEMO_LICENSE_HEADER_VALUE',
-  LICENSE_SERVER_URL: 'DEMO_LICENSE_SERVER_URL',
-  MAIN_TAB: 'DEMO_MAIN_TAB',
-  MANIFEST_URL: 'DEMO_MANIFEST_URL',
-  MANIFEST_URL_ERROR: 'DEMO_MANIFEST_URL_ERROR',
-  NAME: 'DEMO_NAME',
-  NAME_ERROR: 'DEMO_NAME_ERROR',
-  EXTRA_SHAKA_PLAYER_CONFIG: 'DEMO_EXTRA_SHAKA_PLAYER_CONFIG',
-  EXTRA_TAB: 'DEMO_EXTRA_TAB',
-  INVALID_JSON_CONFIG_ERROR: 'DEMO_INVALID_JSON_CONFIG_ERROR',
-  MIME_TYPE: 'DEMO_MIME_TYPE',
-  SAVE_BUTTON: 'DEMO_SAVE_BUTTON',
-  /* Search panel. */
-  AD_SEARCH: 'DEMO_AD_SEARCH',
-  AUDIO_ONLY_SEARCH: 'DEMO_AUDIO_ONLY_SEARCH',
-  CONTAINER_SEARCH: 'DEMO_CONTAINER_SEARCH',
-  DRM_SEARCH: 'DEMO_DRM_SEARCH',
-  HIGH_DEFINITION_SEARCH: 'DEMO_HIGH_DEFINITION_SEARCH',
-  LIVE_SEARCH: 'DEMO_LIVE_SEARCH',
-  MANIFEST_SEARCH: 'DEMO_MANIFEST_SEARCH',
-  OFFLINE_SEARCH: 'DEMO_OFFLINE_SEARCH',
-  STORED_SEARCH: 'DEMO_STORED_SEARCH',
-  SUBTITLES_SEARCH: 'DEMO_SUBTITLES_SEARCH',
-  SURROUND_SEARCH: 'DEMO_SURROUND_SEARCH',
-  SOURCE_SEARCH: 'DEMO_SOURCE_SEARCH',
-  TRICK_MODE_SEARCH: 'DEMO_TRICK_MODE_SEARCH',
-  XLINK_SEARCH: 'DEMO_XLINK_SEARCH',
-  /* Config panel. */
-  ADAPTATION_RESTRICTIONS_SECTION_HEADER: 'DEMO_ADAPTATION_RESTRICTIONS_SECTION_HEADER',
-  ADAPTATION_SECTION_HEADER: 'DEMO_ADAPTATION_SECTION_HEADER',
-  ADS_SECTION_HEADER: 'DEMO_ADS_SECTION_HEADER',
-  ALWAYS_STREAM_TEXT: 'DEMO_ALWAYS_STREAM_TEXT',
-  ALWAYS_STREAM_TEXT_WARNING: 'DEMO_ALWAYS_STREAM_TEXT_WARNING',
-  AUDIO_CHANNEL_COUNT: 'DEMO_AUDIO_CHANNEL_COUNT',
-  AUDIO_LANGUAGE: 'DEMO_AUDIO_LANGUAGE',
-  AUDIO_LABEL: 'DEMO_AUDIO_LABEL',
-  AUDIO_ROBUSTNESS: 'DEMO_AUDIO_ROBUSTNESS',
-  AUTO_CORRECT_DASH_DRIFT: 'DEMO_AUTO_CORRECT_DASH_DRIFT',
-  AUTO_LOW_LATENCY: 'DEMO_AUTO_LOW_LATENCY',
-  AUTO_SHOW_TEXT: 'DEMO_AUTO_SHOW_TEXT',
-  AUTO_SHOW_TEXT_NEVER: 'DEMO_AUTO_SHOW_TEXT_NEVER',
-  AUTO_SHOW_TEXT_ALWAYS: 'DEMO_AUTO_SHOW_TEXT_ALWAYS',
-  AUTO_SHOW_TEXT_IF_PREFERRED_TEXT_LANGUAGE: 'DEMO_AUTO_SHOW_TEXT_IF_PREFERRED_TEXT_LANGUAGE',
-  AUTO_SHOW_TEXT_IF_SUBTITLES_MAY_BE_NEEDED: 'DEMO_AUTO_SHOW_TEXT_IF_SUBTITLES_MAY_BE_NEEDED',
-  AVAILABILITY_WINDOW_OVERRIDE: 'DEMO_AVAILABILITY_WINDOW_OVERRIDE',
-  BACKOFF_FACTOR: 'DEMO_BACKOFF_FACTOR',
-  BASE_DELAY: 'DEMO_BASE_DELAY',
-  BANDWIDTH_DOWNGRADE: 'DEMO_BANDWIDTH_DOWNGRADE',
-  BANDWIDTH_ESTIMATE: 'DEMO_BANDWIDTH_ESTIMATE',
-  BANDWIDTH_UPGRADE: 'DEMO_BANDWIDTH_UPGRADE',
-  BUFFER_BEHIND: 'DEMO_BUFFER_BEHIND',
-  BUFFERING_GOAL: 'DEMO_BUFFERING_GOAL',
-  CLEAR_BUFFER_SWITCH: 'DEMO_CLEAR_BUFFER_SWITCH',
-  CLOCK_SYNC_URI: 'DEMO_CLOCK_SYNC_URI',
-  CMCD_SECTION_HEADER: 'DEMO_CMCD_SECTION_HEADER',
-  CONNECTION_TIMEOUT: 'DEMO_CONNECTION_TIMEOUT',
-  CONTENT_ID: 'DEMO_CONTENT_ID',
-  CUSTOM_PLAYHEAD_TRACKER: 'DEMO_CUSTOM_PLAYHEAD_TRACKER',
-  DASH_SEQUENCE_MODE: 'DEMO_DASH_SEQUENCE_MODE',
-  DEFAULT_AUDIO_CODEC: 'DEMO_DEFAULT_AUDIO_CODEC',
-  DEFAULT_PRESENTATION_DELAY: 'DEMO_DEFAULT_PRESENTATION_DELAY',
-  DEFAULT_VIDEO_CODEC: 'DEMO_DEFAULT_VIDEO_CODEC',
-  DELAY_LICENSE: 'DEMO_DELAY_LICENSE',
-  DISABLE_AUDIO: 'DEMO_DISABLE_AUDIO',
-  DISABLE_TEXT: 'DEMO_DISABLE_TEXT',
-  DISABLE_THUMBNAILS: 'DEMO_DISABLE_THUMBNAILS',
-  DISABLE_VIDEO: 'DEMO_DISABLE_VIDEO',
-  DISABLE_XLINK_PROCESSING: 'DEMO_DISABLE_XLINK_PROCESSING',
-  DISPATCH_ALL_EMSG_BOXES: 'DEMO_DISPATCH_ALL_EMSG_BOXES',
-  OBSERVE_QUALITY_CHANGES: 'DEMO_OBSERVE_QUALITY_CHANGES',
-  DRM_RETRY_SECTION_HEADER: 'DEMO_DRM_RETRY_SECTION_HEADER',
-  DRM_SECTION_HEADER: 'DEMO_DRM_SECTION_HEADER',
-  DRM_SESSION_TYPE: 'DEMO_DRM_SESSION_TYPE',
-  DURATION_BACKOFF: 'DEMO_DURATION_BACKOFF',
-  ENABLED: 'DEMO_ENABLED',
-  ENABLE_AUDIO_GROUPS: 'DEMO_ENABLE_AUDIO_GROUPS',
-  FAST_HALF_LIFE: 'DEMO_FAST_HALF_LIFE',
-  FORCE_HTTPS: 'DEMO_FORCE_HTTPS',
-  FORCE_TRANSMUX: 'DEMO_FORCE_TRANSMUX',
-  INSERT_FAKE_ENCRYPTION_IN_INIT: 'DEMO_INSERT_FAKE_ENCRYPTION_IN_INIT',
-  FUZZ_FACTOR: 'DEMO_FUZZ_FACTOR',
-  GAP_DETECTION_THRESHOLD: 'DEMO_GAP_DETECTION_THRESHOLD',
-  GAP_JUMP_TIMER_TIME: 'DEMO_GAP_JUMP_TIMER_TIME',
-  HDR_LEVEL: 'DEMO_HDR_LEVEL',
-  HDR_LEVEL_AUTO: 'DEMO_HDR_LEVEL_AUTO',
-  HDR_LEVEL_HLG: 'DEMO_HDR_LEVEL_HLG',
-  HDR_LEVEL_NONE: 'DEMO_HDR_LEVEL_NONE',
-  HDR_LEVEL_PQ: 'DEMO_HDR_LEVEL_PQ',
-  HDR_LEVEL_SDR: 'DEMO_HDR_LEVEL_SDR',
-  HLS_SEQUENCE_MODE: 'DEMO_HLS_SEQUENCE_MODE',
-  IGNORE_DASH_EMPTY_ADAPTATION_SET: 'DEMO_IGNORE_DASH_EMPTY_ADAPTATION_SET',
-  IGNORE_DASH_DRM: 'DEMO_IGNORE_DASH_DRM',
-  IGNORE_DASH_MAX_SEGMENT_DURATION: 'DEMO_IGNORE_DASH_MAX_SEGMENT_DURATION',
-  IGNORE_DASH_SUGGESTED_PRESENTATION_DELAY: 'DEMO_IGNORE_DASH_SUGGESTED_PRESENTATION_DELAY',
-  IGNORE_DEVICE_PIXEL_RATIO: 'DEMO_IGNORE_DEVICE_PIXEL_RATIO',
-  IGNORE_HLS_IMAGE_FAILURES: 'DEMO_IGNORE_HLS_IMAGE_FAILURES',
-  IGNORE_HLS_TEXT_FAILURES: 'DEMO_IGNORE_HLS_TEXT_FAILURES',
-  IGNORE_MANIFEST_PROGRAM_DATE_TIME: 'DEMO_IGNORE_MANIFEST_PROGRAM_DATE_TIME',
-  IGNORE_MANIFEST_TIMESTAMPS_IN_SEGMENTS_MODE: 'DEMO_IGNORE_MANIFEST_TIMESTAMPS_IN_SEGMENTS_MODE',
-  IGNORE_MIN_BUFFER_TIME: 'DEMO_IGNORE_MIN_BUFFER_TIME',
-  IGNORE_TEXT_FAILURES: 'DEMO_IGNORE_TEXT_FAILURES',
-  INACCURATE_MANIFEST_TOLERANCE: 'DEMO_INACCURATE_MANIFEST_TOLERANCE',
-  INITIAL_SEGMENT_LIMIT: 'DEMO_INITIAL_SEGMENT_LIMIT',
-  LANGUAGE_SECTION_HEADER: 'DEMO_LANGUAGE_SECTION_HEADER',
-  LCEVC_DRAW_LOGO: 'DEMO_LCEVC_DRAW_LOGO',
-  LCEVC_DYNAMIC_PERFORMANCE_SCALING: 'DEMO_LCEVC_DYNAMIC_PERFORMANCE_SCALING',
-  LCEVC_LOG_LEVEL: 'DEMO_LCEVC_LOG_LEVEL',
-  LCEVC_SECTION_HEADER: 'DEMO_LCEVC_SECTION_HEADER',
-  LIVE_SEGMENTS_DELAY: 'DEMO_LIVE_SEGMENTS_DELAY',
-  LIVE_SYNC: 'DEMO_LIVE_SYNC',
-  LIVE_SYNC_MAX_LATENCY: 'DEMO_LIVE_SYNC_MAX_LATENCY',
-  LIVE_SYNC_PLAYBACK_RATE: 'DEMO_LIVE_SYNC_PLAYBACK_RATE',
-  LOG_LEVEL: 'DEMO_LOG_LEVEL',
-  LOG_LEVEL_DEBUG: 'DEMO_LOG_LEVEL_DEBUG',
-  LOG_LEVEL_INFO: 'DEMO_LOG_LEVEL_INFO',
-  LOG_LEVEL_V: 'DEMO_LOG_LEVEL_V',
-  LOG_LEVEL_VV: 'DEMO_LOG_LEVEL_VV',
-  LOG_LICENSE_EXCHANGE: 'DEMO_LOG_LICENSE_EXCHANGE',
-  LOW_LATENCY: 'DEMO_LOW_LATENCY',
-  MANIFEST_RETRY_SECTION_HEADER: 'DEMO_MANIFEST_RETRY_SECTION_HEADER',
-  MANIFEST_SECTION_HEADER: 'DEMO_MANIFEST_SECTION_HEADER',
-  MAX_ATTEMPTS: 'DEMO_MAX_ATTEMPTS',
-  MAX_BANDWIDTH: 'DEMO_MAX_BANDWIDTH',
-  MAX_DISABLED_TIME: 'DEMO_MAX_DISABLED_TIME',
-  MAX_FRAMERATE: 'DEMO_MAX_FRAMERATE',
-  MAX_HEIGHT: 'DEMO_MAX_HEIGHT',
-  MAX_PIXELS: 'DEMO_MAX_PIXELS',
-  MAX_WIDTH: 'DEMO_MAX_WIDTH',
-  MEDIA_SOURCE_SECTION_HEADER: 'DEMO_MEDIA_SOURCE_SECTION_HEADER',
-  MIN_BANDWIDTH: 'DEMO_MIN_BANDWIDTH',
-  MIN_BYTES: 'DEMO_MIN_BYTES',
-  MIN_HDCP_VERSION: 'DEMO_MIN_HDCP_VERSION',
-  MIN_FRAMERATE: 'DEMO_MIN_FRAMERATE',
-  MIN_HEIGHT: 'DEMO_MIN_HEIGHT',
-  MIN_PIXELS: 'DEMO_MIN_PIXELS',
-  MIN_TOTAL_BYTES: 'DEMO_MIN_TOTAL_BYTES',
-  MIN_WIDTH: 'DEMO_MIN_WIDTH',
-  MSS_SEQUENCE_MODE: 'DEMO_MSS_SEQUENCE_MODE',
-  NETWORK_INFORMATION: 'DEMO_NETWORK_INFORMATION',
-  NUMBER_DECIMAL_WARNING: 'DEMO_NUMBER_DECIMAL_WARNING',
-  NUMBER_INTEGER_WARNING: 'DEMO_NUMBER_INTEGER_WARNING',
-  NUMBER_NONZERO_DECIMAL_WARNING: 'DEMO_NUMBER_NONZERO_DECIMAL_WARNING',
-  NUMBER_NONZERO_INTEGER_WARNING: 'DEMO_NUMBER_NONZERO_INTEGER_WARNING',
-  NUMBER_OF_PARALLEL_DOWNLOADS: 'DEMO_NUMBER_OF_PARALLEL_DOWNLOADS',
-  OFFLINE_SECTION_HEADER: 'DEMO_OFFLINE_SECTION_HEADER',
-  PARSE_INBAND_PSSH_ENABLED: 'DEMO_PARSE_INBAND_PSSH_ENABLED',
-  PREFER_FORCED_SUBS: 'DEMO_PREFER_FORCED_SUBS',
-  PREFER_NATIVE_HLS: 'DEMO_PREFER_NATIVE_HLS',
-  REBUFFERING_GOAL: 'DEMO_REBUFFERING_GOAL',
-  RESTRICT_TO_ELEMENT_SIZE: 'DEMO_RESTRICT_TO_ELEMENT_SIZE',
-  RESTRICT_TO_SCREEN_SIZE: 'DEMO_RESTRICT_TO_SCREEN_SIZE',
-  RESTRICTIONS_SECTION_HEADER: 'DEMO_RESTRICTIONS_SECTION_HEADER',
-  SAFE_MARGIN_SWITCH: 'DEMO_SAFE_MARGIN_SWITCH',
-  SAFE_SEEK_OFFSET: 'DEMO_SAFE_SEEK_OFFSET',
-  SAFE_SKIP_DISTANCE: 'DEMO_SAFE_SKIP_DISTANCE',
-  SEGMENT_RELATIVE_VTT_TIMING: 'DEMO_SEGMENT_RELATIVE_VTT_TIMING',
-  SESSION_ID: 'DEMO_SESSION_ID',
-  SHAKA_CONTROLS: 'DEMO_SHAKA_CONTROLS',
-  SLOW_HALF_LIFE: 'DEMO_SLOW_HALF_LIFE',
-  SOURCE_BUFFER_EXTRA_FEATURES: 'DEMO_SOURCE_BUFFER_EXTRA_FEATURES',
-  STALL_DETECTOR_ENABLED: 'DEMO_STALL_DETECTOR_ENABLED',
-  STALL_THRESHOLD: 'DEMO_STALL_THRESHOLD',
-  STALL_TIMEOUT: 'DEMO_STALL_TIMEOUT',
-  START_AT_SEGMENT_BOUNDARY: 'DEMO_START_AT_SEGMENT_BOUNDARY',
-  STREAMING_RETRY_SECTION_HEADER: 'DEMO_STREAMING_RETRY_SECTION_HEADER',
-  STREAMING_SECTION_HEADER: 'DEMO_STREAMING_SECTION_HEADER',
-  SWITCH_INTERVAL: 'DEMO_SWITCH_INTERVAL',
-  TEXT_LANGUAGE: 'DEMO_TEXT_LANGUAGE',
-  TEXT_ROLE: 'DEMO_TEXT_ROLE',
-  TIMEOUT: 'DEMO_TIMEOUT',
-  TRICK_PLAY_CONTROLS: 'DEMO_TRICK_PLAY_CONTROLS',
-  TRICK_PLAY_CONTROLS_WARNING: 'DEMO_TRICK_PLAY_CONTROLS_WARNING',
-  UI_LOCALE: 'DEMO_UI_LOCALE',
-  UPDATE_EXPIRATION_TIME: 'DEMO_UPDATE_EXPIRATION_TIME',
-  UPDATE_INTERVAL_SECONDS: 'DEMO_UPDATE_INTERVAL_SECONDS',
-  USE_HEADERS: 'DEMO_USE_HEADERS',
-  USE_NATIVE_HLS_SAFARI: 'DEMO_USE_NATIVE_HLS_SAFARI',
-  USE_PERSISTENT_LICENSES: 'DEMO_USE_PERSISTENT_LICENSES',
-  USE_SAFARI_BEHAVIOR_FOR_LIVE: 'DEMO_USE_SAFARI_BEHAVIOR_FOR_LIVE',
-  VIDEO_ROBUSTNESS: 'DEMO_VIDEO_ROBUSTNESS',
-  VNOVA: 'DEMO_VNOVA',
-  XLINK_FAIL_GRACEFULLY: 'DEMO_XLINK_FAIL_GRACEFULLY',
-  SEGMENT_PREFETCH_LIMIT: 'DEMO_SEGMENT_PREFETCH_LIMIT',
-};
-/* eslint-enable max-len */
diff --git a/demo/config.js b/demo/config.js
index 1fc78b28e..c3256dd4d 100644
--- a/demo/config.js
+++ b/demo/config.js
@@ -11,7 +11,6 @@ goog.require('goog.asserts');
 goog.require('shakaDemo.BoolInput');
 goog.require('shakaDemo.DatalistInput');
 goog.require('shakaDemo.InputContainer');
-goog.require('shakaDemo.MessageIds');
 goog.require('shakaDemo.NumberInput');
 goog.require('shakaDemo.SelectInput');
 goog.require('shakaDemo.TextInput');
@@ -58,11 +57,6 @@ shakaDemo.Config = class {
       // changes based on the config changes.
       this.reloadAndSaveState_();
     });
-    document.addEventListener('shaka-main-locale-changed', () => {
-      // Respond to them by remaking. This is to avoid triggering any config
-      // changes based on the config changes.
-      this.reloadAndSaveState_();
-    });
     document.addEventListener('shaka-main-drawer-state-change', () => {
       this.setContentAvailability_(shakaDemoMain.getIsDrawerOpen());
     });
@@ -94,8 +88,7 @@ shakaDemo.Config = class {
     this.addStreamingSection_();
     this.addMediaSourceSection_();
     this.addManifestSection_();
-    this.addRetrictionsSection_('',
-        shakaDemo.MessageIds.RESTRICTIONS_SECTION_HEADER);
+    this.addRetrictionsSection_('', 'Restrictions');
     this.addCmcdSection_();
     this.addLcevcSection_();
     this.addAdsSection_();
@@ -123,22 +116,19 @@ shakaDemo.Config = class {
 
   /** @private */
   addDrmSection_() {
-    const MessageIds = shakaDemo.MessageIds;
     const docLink = this.resolveExternLink_('.DrmConfiguration');
-    this.addSection_(MessageIds.DRM_SECTION_HEADER, docLink)
-        .addBoolInput_(MessageIds.DELAY_LICENSE,
+    this.addSection_('DRM', docLink)
+        .addBoolInput_('Delay License Request Until Played',
             'drm.delayLicenseRequestUntilPlayed')
-        .addBoolInput_(MessageIds.LOG_LICENSE_EXCHANGE,
-            'drm.logLicenseExchange')
-        .addNumberInput_(MessageIds.UPDATE_EXPIRATION_TIME,
+        .addBoolInput_('Log license exchange data', 'drm.logLicenseExchange')
+        .addNumberInput_('Update expiration time',
             'drm.updateExpirationTime',
             /* canBeDecimal= */ true,
             /* canBeZero= */ false,
             /* canBeUnset= */ true)
-        .addBoolInput_(MessageIds.PARSE_INBAND_PSSH_ENABLED,
+        .addBoolInput_('Parse inband "pssh" from media segments',
             'drm.parseInbandPsshEnabled')
-        .addTextInput_(MessageIds.MIN_HDCP_VERSION,
-            'drm.minHdcpVersion');
+        .addTextInput_('Min HDCP version', 'drm.minHdcpVersion');
     const advanced = shakaDemoMain.getConfiguration().drm.advanced || {};
     const addDRMAdvancedField = (name, valueName, suggestions) => {
       // All advanced fields of a given type are set at once.
@@ -177,301 +167,254 @@ shakaDemo.Config = class {
     const sessionTypeSuggestions = ['temporary', 'persistent-license'];
 
     addDRMAdvancedField(
-        MessageIds.VIDEO_ROBUSTNESS,
-        'videoRobustness',
-        robustnessSuggestions);
+        'Video Robustness', 'videoRobustness', robustnessSuggestions);
     addDRMAdvancedField(
-        MessageIds.AUDIO_ROBUSTNESS,
-        'audioRobustness',
-        robustnessSuggestions);
-    addDRMAdvancedField(
-        MessageIds.DRM_SESSION_TYPE,
-        'sessionType',
-        sessionTypeSuggestions);
+        'Audio Robustness', 'audioRobustness', robustnessSuggestions);
+    addDRMAdvancedField('Session Type', 'sessionType', sessionTypeSuggestions);
 
-    this.addRetrySection_('drm', MessageIds.DRM_RETRY_SECTION_HEADER);
+    this.addRetrySection_('drm', 'DRM Retry Parameters');
   }
 
   /** @private */
   addManifestSection_() {
-    const MessageIds = shakaDemo.MessageIds;
     const docLink = this.resolveExternLink_('.ManifestConfiguration');
-    this.addSection_(MessageIds.MANIFEST_SECTION_HEADER, docLink)
-        .addBoolInput_(MessageIds.IGNORE_DASH_DRM,
-            'manifest.dash.ignoreDrmInfo')
-        .addBoolInput_(MessageIds.AUTO_CORRECT_DASH_DRIFT,
+    this.addSection_('Manifest', docLink)
+        .addBoolInput_('Ignore DASH DRM Info', 'manifest.dash.ignoreDrmInfo')
+        .addBoolInput_('Auto-Correct DASH Drift',
             'manifest.dash.autoCorrectDrift')
-        .addBoolInput_(MessageIds.DISABLE_XLINK_PROCESSING,
+        .addBoolInput_('Disable Xlink processing',
             'manifest.dash.disableXlinkProcessing')
-        .addBoolInput_(MessageIds.XLINK_FAIL_GRACEFULLY,
+        .addBoolInput_('Xlink Should Fail Gracefully',
             'manifest.dash.xlinkFailGracefully')
-        .addBoolInput_(MessageIds.IGNORE_DASH_SUGGESTED_PRESENTATION_DELAY,
+        .addBoolInput_('Ignore DASH suggestedPresentationDelay',
             'manifest.dash.ignoreSuggestedPresentationDelay')
-        .addBoolInput_(MessageIds.IGNORE_DASH_EMPTY_ADAPTATION_SET,
+        .addBoolInput_('Ignore empty DASH AdaptationSets',
             'manifest.dash.ignoreEmptyAdaptationSet')
-        .addBoolInput_(MessageIds.IGNORE_DASH_MAX_SEGMENT_DURATION,
+        .addBoolInput_('Ignore DASH maxSegmentDuration',
             'manifest.dash.ignoreMaxSegmentDuration')
-        .addBoolInput_(MessageIds.IGNORE_HLS_TEXT_FAILURES,
+        .addBoolInput_('Ignore HLS Text Stream Failures',
             'manifest.hls.ignoreTextStreamFailures')
-        .addBoolInput_(MessageIds.IGNORE_HLS_IMAGE_FAILURES,
+        .addBoolInput_('Ignore HLS Image Stream Failures',
             'manifest.hls.ignoreImageStreamFailures')
-        .addTextInput_(MessageIds.DEFAULT_AUDIO_CODEC,
-            'manifest.hls.defaultAudioCodec')
-        .addTextInput_(MessageIds.DEFAULT_VIDEO_CODEC,
-            'manifest.hls.defaultVideoCodec')
-        .addBoolInput_(MessageIds.IGNORE_MANIFEST_PROGRAM_DATE_TIME,
+        .addTextInput_('Default Audio Codec', 'manifest.hls.defaultAudioCodec')
+        .addTextInput_('Default Video Codec', 'manifest.hls.defaultVideoCodec')
+        .addBoolInput_('Ignore Program Date Time from manifest',
             'manifest.hls.ignoreManifestProgramDateTime')
-        .addBoolInput_(MessageIds.USE_SAFARI_BEHAVIOR_FOR_LIVE,
+        .addBoolInput_('Use Safari behavior for live',
             'manifest.hls.useSafariBehaviorForLive')
-        .addNumberInput_(MessageIds.LIVE_SEGMENTS_DELAY,
+        .addNumberInput_('Live segments delay',
             'manifest.hls.liveSegmentsDelay')
-        .addBoolInput_(MessageIds.HLS_SEQUENCE_MODE,
-            'manifest.hls.sequenceMode')
-        .addBoolInput_(MessageIds.IGNORE_MANIFEST_TIMESTAMPS_IN_SEGMENTS_MODE,
+        .addBoolInput_('Enable HLS sequence mode', 'manifest.hls.sequenceMode')
+        .addBoolInput_('Ignore Manifest Timestamps in Segments Mode',
             'manifest.hls.ignoreManifestTimestampsInSegmentsMode')
-        .addNumberInput_(MessageIds.AVAILABILITY_WINDOW_OVERRIDE,
+        .addNumberInput_('Availability Window Override',
             'manifest.availabilityWindowOverride',
             /* canBeDecimal= */ true,
             /* canBeZero= */ false,
             /* canBeUnset= */ true)
-        .addTextInput_(MessageIds.CLOCK_SYNC_URI, 'manifest.dash.clockSyncUri')
-        .addNumberInput_(MessageIds.DEFAULT_PRESENTATION_DELAY,
+        .addTextInput_('Clock Sync URI', 'manifest.dash.clockSyncUri')
+        .addNumberInput_('Default Presentation Delay',
             'manifest.defaultPresentationDelay')
-        .addBoolInput_(MessageIds.ENABLE_AUDIO_GROUPS,
-            'manifest.dash.enableAudioGroups')
-        .addBoolInput_(MessageIds.IGNORE_MIN_BUFFER_TIME,
+        .addBoolInput_('Enable Audio Groups', 'manifest.dash.enableAudioGroups')
+        .addBoolInput_('Ignore Min Buffer Time',
             'manifest.dash.ignoreMinBufferTime')
-        .addNumberInput_(MessageIds.INITIAL_SEGMENT_LIMIT,
+        .addNumberInput_('Initial Segment Limit',
             'manifest.dash.initialSegmentLimit',
             /* canBeDecimal= */ false,
             /* canBeZero= */ false,
             /* canBeUnset= */ true)
-        .addBoolInput_(MessageIds.DASH_SEQUENCE_MODE,
+        .addBoolInput_('Enable DASH sequence mode',
             'manifest.dash.sequenceMode')
-        .addBoolInput_(MessageIds.DISABLE_AUDIO,
-            'manifest.disableAudio')
-        .addBoolInput_(MessageIds.DISABLE_VIDEO,
-            'manifest.disableVideo')
-        .addBoolInput_(MessageIds.DISABLE_TEXT,
-            'manifest.disableText')
-        .addBoolInput_(MessageIds.DISABLE_THUMBNAILS,
-            'manifest.disableThumbnails')
-        .addBoolInput_(MessageIds.SEGMENT_RELATIVE_VTT_TIMING,
+        .addBoolInput_('Disable Audio', 'manifest.disableAudio')
+        .addBoolInput_('Disable Video', 'manifest.disableVideo')
+        .addBoolInput_('Disable Text', 'manifest.disableText')
+        .addBoolInput_('Disable Thumbnails', 'manifest.disableThumbnails')
+        .addBoolInput_('Enable segment-relative VTT Timing',
             'manifest.segmentRelativeVttTiming')
-        .addBoolInput_(MessageIds.MSS_SEQUENCE_MODE,
-            'manifest.mss.sequenceMode');
+        .addBoolInput_('Enable MSS sequence mode', 'manifest.mss.sequenceMode');
 
-    this.addRetrySection_('manifest', MessageIds.MANIFEST_RETRY_SECTION_HEADER);
+    this.addRetrySection_('manifest', 'Manifest Retry Parameters');
   }
 
   /** @private */
   addAbrSection_() {
-    const MessageIds = shakaDemo.MessageIds;
     const docLink = this.resolveExternLink_('.AbrConfiguration');
-    this.addSection_(MessageIds.ADAPTATION_SECTION_HEADER, docLink)
-        .addBoolInput_(MessageIds.ENABLED, 'abr.enabled')
-        .addBoolInput_(MessageIds.NETWORK_INFORMATION,
+    this.addSection_('Adaptation', docLink)
+        .addBoolInput_('Enabled', 'abr.enabled')
+        .addBoolInput_('Use Network Information API',
             'abr.useNetworkInformation')
-        .addNumberInput_(MessageIds.BANDWIDTH_ESTIMATE,
+        .addNumberInput_('Default Bandwidth EstimatZ',
             'abr.defaultBandwidthEstimate')
-        .addNumberInput_(MessageIds.BANDWIDTH_DOWNGRADE,
+        .addNumberInput_('Bandwidth Downgrade Target',
             'abr.bandwidthDowngradeTarget',
             /* canBeDecimal= */ true)
-        .addNumberInput_(MessageIds.BANDWIDTH_UPGRADE,
+        .addNumberInput_('Bandwidth Upgrade Target',
             'abr.bandwidthUpgradeTarget',
             /* canBeDecimal= */ true)
-        .addNumberInput_(MessageIds.SWITCH_INTERVAL,
-            'abr.switchInterval',
+        .addNumberInput_('Switch Interval', 'abr.switchInterval',
             /* canBeDecimal= */ true)
-        .addNumberInput_(MessageIds.MIN_TOTAL_BYTES,
-            'abr.advanced.minTotalBytes')
-        .addNumberInput_(MessageIds.MIN_BYTES,
-            'abr.advanced.minBytes')
-        .addNumberInput_(MessageIds.FAST_HALF_LIFE,
-            'abr.advanced.fastHalfLife',
+        .addNumberInput_('Min total Bytes', 'abr.advanced.minTotalBytes')
+        .addNumberInput_('Min Bytes', 'abr.advanced.minBytes')
+        .addNumberInput_('Fast half life', 'abr.advanced.fastHalfLife',
             /* canBeDecimal= */ true)
-        .addNumberInput_(MessageIds.SLOW_HALF_LIFE,
-            'abr.advanced.slowHalfLife',
+        .addNumberInput_('Slow half life', 'abr.advanced.slowHalfLife',
             /* canBeDecimal= */ true)
-        .addBoolInput_(MessageIds.RESTRICT_TO_ELEMENT_SIZE,
-            'abr.restrictToElementSize')
-        .addBoolInput_(MessageIds.RESTRICT_TO_SCREEN_SIZE,
-            'abr.restrictToScreenSize')
-        .addBoolInput_(MessageIds.IGNORE_DEVICE_PIXEL_RATIO,
+        .addBoolInput_('Restrict to element size', 'abr.restrictToElementSize')
+        .addBoolInput_('Restrict to screen size', 'abr.restrictToScreenSize')
+        .addBoolInput_('Ignore device pixel ratio',
             'abr.ignoreDevicePixelRatio')
-        .addBoolInput_(MessageIds.CLEAR_BUFFER_SWITCH,
+        .addBoolInput_('Clear video buffer on abr rendition switch',
             'abr.clearBufferSwitch')
-        .addNumberInput_(MessageIds.SAFE_MARGIN_SWITCH,
+        .addNumberInput_('Safe margin on abr switch rendition',
             'abr.safeMarginSwitch',
             /* canBeDecimal= */ true);
-    this.addRetrictionsSection_('abr',
-        MessageIds.ADAPTATION_RESTRICTIONS_SECTION_HEADER);
+    this.addRetrictionsSection_('abr', 'Adaptation Restrictions');
   }
 
   /** @private */
   addCmcdSection_() {
-    const MessageIds = shakaDemo.MessageIds;
     const docLink = this.resolveExternLink_('.CmcdConfiguration');
-    this.addSection_(MessageIds.CMCD_SECTION_HEADER, docLink)
-        .addBoolInput_(MessageIds.ENABLED, 'cmcd.enabled')
-        .addTextInput_(MessageIds.SESSION_ID, 'cmcd.sessionId')
-        .addTextInput_(MessageIds.CONTENT_ID, 'cmcd.contentId')
-        .addBoolInput_(MessageIds.USE_HEADERS, 'cmcd.useHeaders');
+    this.addSection_('CMCD', docLink)
+        .addBoolInput_('Enabled', 'cmcd.enabled')
+        .addTextInput_('Session ID', 'cmcd.sessionId')
+        .addTextInput_('Content ID', 'cmcd.contentId')
+        .addBoolInput_('Use Headers', 'cmcd.useHeaders');
   }
 
   /** @private */
   addLcevcSection_() {
-    const MessageIds = shakaDemo.MessageIds;
     const docLink = this.resolveExternLink_('.LcevcConfiguration');
-    this.addSection_(MessageIds.LCEVC_SECTION_HEADER, docLink)
-        .addBoolInput_(MessageIds.ENABLED, 'lcevc.enabled')
-        .addBoolInput_(MessageIds.LCEVC_DYNAMIC_PERFORMANCE_SCALING,
+    this.addSection_('MPEG-5 Part-2 LCEVC', docLink)
+        .addBoolInput_('Enabled', 'lcevc.enabled')
+        .addBoolInput_('LCEVC Dynamic Performance scaling',
             'lcevc.dynamicPerformanceScaling')
-        .addNumberInput_(MessageIds.LCEVC_LOG_LEVEL, 'lcevc.logLevel')
-        .addBoolInput_(MessageIds.LCEVC_DRAW_LOGO, 'lcevc.drawLogo');
+        .addNumberInput_('LCEVC Log Level', 'lcevc.logLevel')
+        .addBoolInput_('Draw LCEVC Logo', 'lcevc.drawLogo');
   }
 
   /** @private */
   addAdsSection_() {
-    const MessageIds = shakaDemo.MessageIds;
     const docLink = this.resolveExternLink_('.AdsConfiguration');
-    this.addSection_(MessageIds.ADS_SECTION_HEADER, docLink)
-        .addBoolInput_(MessageIds.CUSTOM_PLAYHEAD_TRACKER,
+    this.addSection_('Ads', docLink)
+        .addBoolInput_('Custom playhead tracker',
             'ads.customPlayheadTracker');
   }
 
   /**
    * @param {string} category
-   * @param {!shakaDemo.MessageIds} sectionName
+   * @param {string} sectionName
    * @private
    */
   addRetrictionsSection_(category, sectionName) {
-    const MessageIds = shakaDemo.MessageIds;
     const prefix = (category ? category + '.' : '') + 'restrictions.';
     const docLink = this.resolveExternLink_('.Restrictions');
     this.addSection_(sectionName, docLink)
-        .addNumberInput_(MessageIds.MIN_WIDTH, prefix + 'minWidth')
-        .addNumberInput_(MessageIds.MAX_WIDTH, prefix + 'maxWidth')
-        .addNumberInput_(MessageIds.MIN_HEIGHT, prefix + 'minHeight')
-        .addNumberInput_(MessageIds.MAX_HEIGHT, prefix + 'maxHeight')
-        .addNumberInput_(MessageIds.MIN_PIXELS, prefix + 'minPixels')
-        .addNumberInput_(MessageIds.MAX_PIXELS, prefix + 'maxPixels')
-        .addNumberInput_(MessageIds.MIN_FRAMERATE, prefix + 'minFrameRate')
-        .addNumberInput_(MessageIds.MAX_FRAMERATE, prefix + 'maxFrameRate')
-        .addNumberInput_(MessageIds.MIN_BANDWIDTH, prefix + 'minBandwidth')
-        .addNumberInput_(MessageIds.MAX_BANDWIDTH, prefix + 'maxBandwidth');
+        .addNumberInput_('Min Width', prefix + 'minWidth')
+        .addNumberInput_('Max Width', prefix + 'maxWidth')
+        .addNumberInput_('Min Height', prefix + 'minHeight')
+        .addNumberInput_('Max Height', prefix + 'maxHeight')
+        .addNumberInput_('Min Pixels', prefix + 'minPixels')
+        .addNumberInput_('Max Pixels', prefix + 'maxPixels')
+        .addNumberInput_('Min Framerate', prefix + 'minFrameRate')
+        .addNumberInput_('Max Framerate', prefix + 'maxFrameRate')
+        .addNumberInput_('Min Bandwidth', prefix + 'minBandwidth')
+        .addNumberInput_('Max Bandwidth', prefix + 'maxBandwidth');
   }
 
   /**
    * @param {string} category
-   * @param {!shakaDemo.MessageIds} sectionName
+   * @param {string} sectionName
    * @private
    */
   addRetrySection_(category, sectionName) {
-    const MessageIds = shakaDemo.MessageIds;
     const prefix = category + '.retryParameters.';
     const docLink = this.resolveExternLink_('.RetryParameters');
     this.addSection_(sectionName, docLink)
-        .addNumberInput_(MessageIds.MAX_ATTEMPTS, prefix + 'maxAttempts')
-        .addNumberInput_(MessageIds.BASE_DELAY, prefix + 'baseDelay',
+        .addNumberInput_('Max Attempts', prefix + 'maxAttempts')
+        .addNumberInput_('Base Delay', prefix + 'baseDelay',
             /* canBeDecimal= */ true)
-        .addNumberInput_(MessageIds.BACKOFF_FACTOR, prefix + 'backoffFactor',
+        .addNumberInput_('Backoff Factor', prefix + 'backoffFactor',
             /* canBeDecimal= */ true)
-        .addNumberInput_(MessageIds.FUZZ_FACTOR, prefix + 'fuzzFactor',
+        .addNumberInput_('Fuzz Factor', prefix + 'fuzzFactor',
             /* canBeDecimal= */ true)
-        .addNumberInput_(MessageIds.TIMEOUT, prefix + 'timeout',
+        .addNumberInput_('Timeout Factor', prefix + 'timeout',
             /* canBeDecimal= */ true)
-        .addNumberInput_(MessageIds.STALL_TIMEOUT, prefix + 'stallTimeout',
+        .addNumberInput_('Stall Timeout', prefix + 'stallTimeout',
             /* canBeDecimal= */ true)
-        .addNumberInput_(MessageIds.CONNECTION_TIMEOUT,
-            prefix + 'connectionTimeout',
+        .addNumberInput_('Connection Timeout', prefix + 'connectionTimeout',
             /* canBeDecimal= */ true);
   }
 
   /** @private */
   addOfflineSection_() {
-    const MessageIds = shakaDemo.MessageIds;
     const docLink = this.resolveExternLink_('.OfflineConfiguration');
-    this.addSection_(MessageIds.OFFLINE_SECTION_HEADER, docLink)
-        .addBoolInput_(MessageIds.USE_PERSISTENT_LICENSES,
+    this.addSection_('Offline', docLink)
+        .addBoolInput_('Use Persistent Licenses',
             'offline.usePersistentLicense')
-        .addNumberInput_(MessageIds.NUMBER_OF_PARALLEL_DOWNLOADS,
+        .addNumberInput_('Number of Parallel Downloads',
             'offline.numberOfParallelDownloads');
   }
 
   /** @private */
   addStreamingSection_() {
-    const MessageIds = shakaDemo.MessageIds;
     const docLink = this.resolveExternLink_('.StreamingConfiguration');
-    this.addSection_(MessageIds.STREAMING_SECTION_HEADER, docLink)
-        .addNumberInput_(MessageIds.GAP_DETECTION_THRESHOLD,
+    this.addSection_('Streaming', docLink)
+        .addNumberInput_('Gap detection threshold',
             'streaming.gapDetectionThreshold',
             /* canBeDecimal= */ true)
-        .addNumberInput_(MessageIds.GAP_JUMP_TIMER_TIME,
-            'streaming.gapJumpTimerTime',
+        .addNumberInput_('Gap Jump Timer Time', 'streaming.gapJumpTimerTime',
             /* canBeDecimal= */ true)
-        .addNumberInput_(MessageIds.BUFFERING_GOAL,
-            'streaming.bufferingGoal',
+        .addNumberInput_('Buffering Goal', 'streaming.bufferingGoal',
             /* canBeDecimal= */ true)
-        .addNumberInput_(MessageIds.DURATION_BACKOFF,
-            'streaming.durationBackoff',
+        .addNumberInput_('Duration Backoff', 'streaming.durationBackoff',
             /* canBeDecimal= */ true)
-        .addNumberInput_(MessageIds.REBUFFERING_GOAL,
-            'streaming.rebufferingGoal',
+        .addNumberInput_('Rebuffering Goal', 'streaming.rebufferingGoal',
             /* canBeDecimal= */ true)
-        .addNumberInput_(MessageIds.BUFFER_BEHIND,
-            'streaming.bufferBehind',
+        .addNumberInput_('Buffer Behind', 'streaming.bufferBehind',
             /* canBeDecimal= */ true)
-        .addNumberInput_(MessageIds.SAFE_SEEK_OFFSET,
-            'streaming.safeSeekOffset',
+        .addNumberInput_('Safe Seek Offset', 'streaming.safeSeekOffset',
             /* canBeDecimal= */ true)
-        .addNumberInput_(MessageIds.STALL_THRESHOLD,
-            'streaming.stallThreshold',
+        .addNumberInput_('Stall Threshold', 'streaming.stallThreshold',
             /* canBeDecimal= */ true)
-        .addNumberInput_(MessageIds.SAFE_SKIP_DISTANCE,
-            'streaming.stallSkip',
+        .addNumberInput_('Safe Skip Distance', 'streaming.stallSkip',
             /* canBeDecimal= */ true)
-        .addNumberInput_(MessageIds.INACCURATE_MANIFEST_TOLERANCE,
+        .addNumberInput_('Inaccurate Manifest Tolerance',
             'streaming.inaccurateManifestTolerance',
             /* canBeDecimal= */ true)
-        .addBoolInput_(MessageIds.LOW_LATENCY,
-            'streaming.lowLatencyMode')
-        .addBoolInput_(MessageIds.AUTO_LOW_LATENCY,
-            'streaming.autoLowLatencyMode')
-        .addBoolInput_(MessageIds.FORCE_HTTPS,
-            'streaming.forceHTTPS')
-        .addBoolInput_(MessageIds.PREFER_NATIVE_HLS,
+        .addBoolInput_('Low Latency Mode', 'streaming.lowLatencyMode')
+        .addBoolInput_('Auto Low Latency Mode', 'streaming.autoLowLatencyMode')
+        .addBoolInput_('Force HTTPS', 'streaming.forceHTTPS')
+        .addBoolInput_('Prefer native HLS playback when available',
             'streaming.preferNativeHls')
-        .addNumberInput_(MessageIds.UPDATE_INTERVAL_SECONDS,
+        .addNumberInput_('Update interval seconds',
             'streaming.updateIntervalSeconds',
             /* canBeDecimal= */ true)
-        .addBoolInput_(MessageIds.DISPATCH_ALL_EMSG_BOXES,
+        .addBoolInput_('Dispatch all emsg boxes',
             'streaming.dispatchAllEmsgBoxes')
-        .addBoolInput_(MessageIds.OBSERVE_QUALITY_CHANGES,
+        .addBoolInput_('Observe media quality changes',
             'streaming.observeQualityChanges')
-        .addNumberInput_(MessageIds.MAX_DISABLED_TIME,
+        .addNumberInput_('Max Variant Disabled Time',
             'streaming.maxDisabledTime')
-        .addNumberInput_(MessageIds.SEGMENT_PREFETCH_LIMIT,
+        .addNumberInput_('Segment Prefetch Limit',
             'streaming.segmentPrefetchLimit')
-        .addBoolInput_(MessageIds.LIVE_SYNC,
-            'streaming.liveSync')
-        .addNumberInput_(MessageIds.LIVE_SYNC_MAX_LATENCY,
+        .addBoolInput_('Live Sync', 'streaming.liveSync')
+        .addNumberInput_('Max latency for live sync',
             'streaming.liveSyncMaxLatency',
             /* canBeDecimal= */ true,
             /* canBeZero= */ true)
-        .addNumberInput_(MessageIds.LIVE_SYNC_PLAYBACK_RATE,
+        .addNumberInput_('Playback rate for live sync',
             'streaming.liveSyncPlaybackRate',
             /* canBeDecimal= */ true,
             /* canBeZero= */ false);
 
     if (!shakaDemoMain.getNativeControlsEnabled()) {
-      this.addBoolInput_(MessageIds.ALWAYS_STREAM_TEXT,
-          'streaming.alwaysStreamText');
+      this.addBoolInput_('Always Stream Text', 'streaming.alwaysStreamText');
     } else {
       // Add a fake custom fixed "input" that warns the users not to change it.
       const noop = (input) => {};
-      this.addCustomBoolInput_(MessageIds.ALWAYS_STREAM_TEXT,
-          noop, MessageIds.ALWAYS_STREAM_TEXT_WARNING);
+      this.addCustomBoolInput_('Always Stream Text', noop,
+          'Text must always be streamed while native controls are enabled, ' +
+          'for captions to work.');
       this.latestInput_.input().disabled = true;
       this.latestInput_.input().checked = true;
     }
@@ -483,65 +426,55 @@ shakaDemo.Config = class {
       'PQ': 'PQ',
       'HLG': 'HLG',
     };
-    const localize = (name) => shakaDemoMain.getLocalizedString(name);
     const hdrLevelNames = {
-      'AUTO': localize(MessageIds.HDR_LEVEL_AUTO),
-      'SDR': localize(MessageIds.HDR_LEVEL_SDR),
-      'PQ': localize(MessageIds.HDR_LEVEL_PQ),
-      'HLG': localize(MessageIds.HDR_LEVEL_HLG),
-      '': localize(MessageIds.HDR_LEVEL_NONE),
+      'AUTO': 'Auto Detect',
+      'SDR': 'SDR',
+      'PQ': 'PQ',
+      'HLG': 'HLG',
+      '': 'No Preference',
     };
-    this.addSelectInput_(MessageIds.HDR_LEVEL, 'preferredVideoHdrLevel',
+    this.addSelectInput_('Preferred HDR Level', 'preferredVideoHdrLevel',
         hdrLevels, hdrLevelNames);
 
-    this.addBoolInput_(MessageIds.START_AT_SEGMENT_BOUNDARY,
+    this.addBoolInput_('Start At Segment Boundary',
         'streaming.startAtSegmentBoundary')
-        .addBoolInput_(MessageIds.IGNORE_TEXT_FAILURES,
+        .addBoolInput_('Ignore Text Stream Failures',
             'streaming.ignoreTextStreamFailures')
-        .addBoolInput_(MessageIds.STALL_DETECTOR_ENABLED,
-            'streaming.stallEnabled')
-        .addBoolInput_(MessageIds.USE_NATIVE_HLS_SAFARI,
+        .addBoolInput_('Stall Detector Enabled', 'streaming.stallEnabled')
+        .addBoolInput_('Use native HLS on Safari',
             'streaming.useNativeHlsOnSafari');
-    this.addRetrySection_('streaming',
-        MessageIds.STREAMING_RETRY_SECTION_HEADER);
+    this.addRetrySection_('streaming', 'Streaming Retry Parameters');
   }
 
   /** @private */
   addMediaSourceSection_() {
-    const MessageIds = shakaDemo.MessageIds;
     const docLink = this.resolveExternLink_('.MediaSourceConfiguration');
-    this.addSection_(MessageIds.MEDIA_SOURCE_SECTION_HEADER, docLink)
-        .addTextInput_(MessageIds.SOURCE_BUFFER_EXTRA_FEATURES,
+    this.addSection_('Media source', docLink)
+        .addTextInput_('Source buffer extra features',
             'mediaSource.sourceBufferExtraFeatures')
-        .addBoolInput_(MessageIds.FORCE_TRANSMUX,
-            'mediaSource.forceTransmux')
-        .addBoolInput_(MessageIds.INSERT_FAKE_ENCRYPTION_IN_INIT,
-            'mediaSource.insertFakeEncryptionInInit');
+        .addBoolInput_('Force Transmux', 'mediaSource.forceTransmux')
+        .addBoolInput_('Insert fake encryption in init segments when needed ' +
+            'by the platform.', 'mediaSource.insertFakeEncryptionInInit');
   }
 
   /** @private */
   addLanguageSection_() {
-    const MessageIds = shakaDemo.MessageIds;
     const docLink = this.resolveExternLink_('.PlayerConfiguration');
 
     const autoShowTextOptions = shaka.config.AutoShowText;
-    const localize = (name) => shakaDemoMain.getLocalizedString(name);
     const autoShowTextOptionNames = {
-      'NEVER': localize(MessageIds.AUTO_SHOW_TEXT_NEVER),
-      'ALWAYS': localize(MessageIds.AUTO_SHOW_TEXT_ALWAYS),
-      'IF_PREFERRED_TEXT_LANGUAGE':
-          localize(MessageIds.AUTO_SHOW_TEXT_IF_PREFERRED_TEXT_LANGUAGE),
-      'IF_SUBTITLES_MAY_BE_NEEDED':
-          localize(MessageIds.AUTO_SHOW_TEXT_IF_SUBTITLES_MAY_BE_NEEDED),
+      'NEVER': 'Never',
+      'ALWAYS': 'Always',
+      'IF_PREFERRED_TEXT_LANGUAGE': 'If preferred text language',
+      'IF_SUBTITLES_MAY_BE_NEEDED': 'If subtitles may be needed',
     };
 
-    this.addSection_(MessageIds.LANGUAGE_SECTION_HEADER, docLink)
-        .addTextInput_(MessageIds.AUDIO_LANGUAGE, 'preferredAudioLanguage')
-        .addTextInput_(MessageIds.AUDIO_LABEL, 'preferredAudioLabel')
-        .addTextInput_(MessageIds.TEXT_LANGUAGE, 'preferredTextLanguage')
-        .addTextInput_(MessageIds.TEXT_ROLE, 'preferredTextRole')
-        .addSelectInput_(
-            MessageIds.AUTO_SHOW_TEXT,
+    this.addSection_('Language', docLink)
+        .addTextInput_('Preferred Audio Language', 'preferredAudioLanguage')
+        .addTextInput_('Preferred Audio Label', 'preferredAudioLabel')
+        .addTextInput_('Preferred Text Language', 'preferredTextLanguage')
+        .addTextInput_('Preferred Text Role', 'preferredTextRole')
+        .addSelectInput_('Auto-Show Text',
             'autoShowText',
             autoShowTextOptions,
             autoShowTextOptionNames);
@@ -549,20 +482,18 @@ shakaDemo.Config = class {
       shakaDemoMain.setUILocale(input.value);
       shakaDemoMain.remakeHash();
     };
-    this.addCustomTextInput_(MessageIds.UI_LOCALE, onChange);
+    this.addCustomTextInput_('Preferred UI Locale', onChange);
     this.latestInput_.input().value = shakaDemoMain.getUILocale();
-    this.addNumberInput_(MessageIds.AUDIO_CHANNEL_COUNT,
+    this.addNumberInput_('Preferred Audio Channel Count',
         'preferredAudioChannelCount');
-    this.addBoolInput_(MessageIds.PREFER_FORCED_SUBS,
-        'preferForcedSubs');
+    this.addBoolInput_('Prefer Forced Subs', 'preferForcedSubs');
   }
 
   /** @private */
   addMetaSection_() {
-    const MessageIds = shakaDemo.MessageIds;
     this.addSection_(/* name= */ null, /* docLink= */ null);
 
-    this.addCustomBoolInput_(MessageIds.SHAKA_CONTROLS, (input) => {
+    this.addCustomBoolInput_('Shaka Controls', (input) => {
       shakaDemoMain.setNativeControlsEnabled(!input.checked);
       if (input.checked) {
         // Forcibly set |streaming.alwaysStreamText| to true.
@@ -580,7 +511,7 @@ shakaDemo.Config = class {
     }
 
     if (!shakaDemoMain.getNativeControlsEnabled()) {
-      this.addCustomBoolInput_(MessageIds.TRICK_PLAY_CONTROLS, (input) => {
+      this.addCustomBoolInput_('Enabled Trick Play Controls', (input) => {
         shakaDemoMain.setTrickPlayControlsEnabled(input.checked);
       });
       if (shakaDemoMain.getTrickPlayControlsEnabled()) {
@@ -589,8 +520,8 @@ shakaDemo.Config = class {
     } else {
       // Add a fake custom fixed "input" that warns the users not to change it.
       const noop = (input) => {};
-      this.addCustomBoolInput_(MessageIds.TRICK_PLAY_CONTROLS,
-          noop, MessageIds.TRICK_PLAY_CONTROLS_WARNING);
+      this.addCustomBoolInput_('Enabled Trick Play Controls',
+          noop, 'Trick Play controls require the Shaka UI.');
       this.latestInput_.input().disabled = true;
       this.latestInput_.input().checked = false;
     }
@@ -610,12 +541,11 @@ shakaDemo.Config = class {
     const Level = shaka['log']['Level'];
     const setLevel = shaka['log']['setLevel'];
 
-    const localize = (name) => shakaDemoMain.getLocalizedString(name);
     const logLevels = {
-      'info': localize(MessageIds.LOG_LEVEL_INFO),
-      'debug': localize(MessageIds.LOG_LEVEL_DEBUG),
-      'v': localize(MessageIds.LOG_LEVEL_V),
-      'vv': localize(MessageIds.LOG_LEVEL_VV),
+      'info': 'Info',
+      'debug': 'Debug',
+      'v': 'Verbose',
+      'vv': 'Very Verbose',
     };
     const onChange = (input) => {
       switch (input.value) {
@@ -634,7 +564,7 @@ shakaDemo.Config = class {
       }
       shakaDemoMain.remakeHash();
     };
-    this.addCustomSelectInput_(MessageIds.LOG_LEVEL, logLevels, onChange);
+    this.addCustomSelectInput_('Log Level', logLevels, onChange);
     const input = this.latestInput_.input();
     switch (shaka['log']['currentLevel']) {
       case Level['DEBUG']:
@@ -662,7 +592,7 @@ shakaDemo.Config = class {
   }
 
   /**
-   * @param {?shakaDemo.MessageIds} name
+   * @param {?string} name
    * @param {?string} docLink
    * @return {!shakaDemo.Config}
    * @private
@@ -678,9 +608,9 @@ shakaDemo.Config = class {
   }
 
   /**
-   * @param {!shakaDemo.MessageIds} name
+   * @param {string} name
    * @param {string} valueName
-   * @param {shakaDemo.MessageIds=} tooltipMessage
+   * @param {string=} tooltipMessage
    * @return {!shakaDemo.Config}
    * @private
    */
@@ -697,24 +627,23 @@ shakaDemo.Config = class {
   }
 
   /**
-   * @param {!shakaDemo.MessageIds} name
+   * @param {string} name
    * @param {function(!HTMLInputElement)} onChange
-   * @param {shakaDemo.MessageIds=} tooltipMessage
+   * @param {string=} tooltipMessage
    * @return {!shakaDemo.Config}
    * @private
    */
   addCustomBoolInput_(name, onChange, tooltipMessage) {
     this.createRow_(name, tooltipMessage);
-    const localized = shakaDemoMain.getLocalizedString(name);
     this.latestInput_ = new shakaDemo.BoolInput(
-        this.getLatestSection_(), localized, onChange);
+        this.getLatestSection_(), name, onChange);
     return this;
   }
 
   /**
-   * @param {!shakaDemo.MessageIds} name
+   * @param {!string} name
    * @param {string} valueName
-   * @param {shakaDemo.MessageIds=} tooltipMessage
+   * @param {string=} tooltipMessage
    * @return {!shakaDemo.Config}
    * @private
    */
@@ -730,27 +659,26 @@ shakaDemo.Config = class {
   }
 
   /**
-   * @param {!shakaDemo.MessageIds} name
+   * @param {string} name
    * @param {function(!HTMLInputElement)} onChange
-   * @param {shakaDemo.MessageIds=} tooltipMessage
+   * @param {string=} tooltipMessage
    * @return {!shakaDemo.Config}
    * @private
    */
   addCustomTextInput_(name, onChange, tooltipMessage) {
     this.createRow_(name, tooltipMessage);
-    const localized = shakaDemoMain.getLocalizedString(name);
     this.latestInput_ = new shakaDemo.TextInput(
-        this.getLatestSection_(), localized, onChange);
+        this.getLatestSection_(), name, onChange);
     return this;
   }
 
   /**
-   * @param {!shakaDemo.MessageIds} name
+   * @param {string} name
    * @param {string} valueName
    * @param {boolean=} canBeDecimal
    * @param {boolean=} canBeZero
    * @param {boolean=} canBeUnset
-   * @param {shakaDemo.MessageIds=} tooltipMessage
+   * @param {string=} tooltipMessage
    * @return {!shakaDemo.Config}
    * @private
    */
@@ -780,9 +708,8 @@ shakaDemo.Config = class {
       }
     };
     this.createRow_(name, tooltipMessage);
-    const localized = shakaDemoMain.getLocalizedString(name);
     this.latestInput_ = new shakaDemo.NumberInput(
-        this.getLatestSection_(), localized, onChange, canBeDecimal, canBeZero,
+        this.getLatestSection_(), name, onChange, canBeDecimal, canBeZero,
         canBeUnset);
     this.latestInput_.input().value =
         shakaDemoMain.getCurrentConfigValue(valueName);
@@ -793,26 +720,25 @@ shakaDemo.Config = class {
   }
 
   /**
-   * @param {!shakaDemo.MessageIds} name
+   * @param {string} name
    * @param {!Array.<string>} values
    * @param {function(!HTMLInputElement)} onChange
-   * @param {shakaDemo.MessageIds=} tooltipMessage
+   * @param {string=} tooltipMessage
    * @return {!shakaDemo.Config}
    * @private
    */
   addDatalistInput_(name, values, onChange, tooltipMessage) {
     this.createRow_(name, tooltipMessage);
-    const localized = shakaDemoMain.getLocalizedString(name);
     this.latestInput_ = new shakaDemo.DatalistInput(
-        this.getLatestSection_(), localized, onChange, values);
+        this.getLatestSection_(), name, onChange, values);
     return this;
   }
 
   /**
-   * @param {!shakaDemo.MessageIds} name
+   * @param {string} name
    * @param {!Object.<string, string>} values
    * @param {function(!HTMLInputElement)} onChange
-   * @param {shakaDemo.MessageIds=} tooltipMessage
+   * @param {string=} tooltipMessage
    * @return {!shakaDemo.Config}
    * @private
    */
@@ -826,11 +752,11 @@ shakaDemo.Config = class {
   }
 
   /**
-   * @param {!shakaDemo.MessageIds} name
+   * @param {string} name
    * @param {string} valueName
    * @param {!Object.<string, ?>} options
    * @param {!Object.<string, string>} optionNames
-   * @param {shakaDemo.MessageIds=} tooltipMessage
+   * @param {string=} tooltipMessage
    * @return {!shakaDemo.Config}
    * @private
    */
@@ -862,8 +788,8 @@ shakaDemo.Config = class {
   }
 
   /**
-   * @param {!shakaDemo.MessageIds} name
-   * @param {shakaDemo.MessageIds=} tooltipMessage
+   * @param {string} name
+   * @param {string=} tooltipMessage
    * @private
    */
   createRow_(name, tooltipMessage) {
diff --git a/demo/custom.js b/demo/custom.js
index dc9588030..dda6cf329 100644
--- a/demo/custom.js
+++ b/demo/custom.js
@@ -12,7 +12,6 @@ goog.require('ShakaDemoAssetInfo');
 goog.require('shakaDemo.AssetCard');
 goog.require('shakaDemo.Input');
 goog.require('shakaDemo.InputContainer');
-goog.require('shakaDemo.MessageIds');
 goog.require('shakaDemo.TextInput');
 
 /** @type {?shakaDemo.Custom} */
@@ -71,9 +70,6 @@ shakaDemo.Custom = class {
     document.addEventListener('shaka-main-offline-progress', () => {
       this.updateOfflineProgress_();
     });
-    document.addEventListener('shaka-main-locale-changed', () => {
-      this.remakeSavedList_();
-    });
     document.addEventListener('shaka-main-page-changed', () => {
       if (!this.savedList_.childNodes.length &&
           !container.classList.contains('hidden')) {
@@ -142,9 +138,8 @@ shakaDemo.Custom = class {
       const div = document.createElement('div');
       headersDiv.appendChild(div);
       const containerStyle = shakaDemo.InputContainer.Style.VERTICAL;
-      const headerText = shakaDemo.MessageIds.LICENSE_HEADER_TITLE;
       const container = new shakaDemo.InputContainer(
-          div, headerText, containerStyle,
+          div, 'License Header', containerStyle,
           /* docLink= */ null);
 
       const collisionCheckEntry = {
@@ -209,9 +204,7 @@ shakaDemo.Custom = class {
       const nameOnChange = (input) => {
         onChange(input.value, headerValue);
       };
-      const licenseHeaderName = shakaDemoMain.getLocalizedString(
-          shakaDemo.MessageIds.LICENSE_HEADER_NAME);
-      this.makeField_(container, licenseHeaderName, nameSetup, nameOnChange);
+      this.makeField_(container, 'Header Name', nameSetup, nameOnChange);
 
       const valueSetup = (input, container) => {
         if (headerValue) {
@@ -221,9 +214,7 @@ shakaDemo.Custom = class {
       const valueOnChange = (input) => {
         onChange(headerName, input.value);
       };
-      const licenseHeaderValue = shakaDemoMain.getLocalizedString(
-          shakaDemo.MessageIds.LICENSE_HEADER_VALUE);
-      this.makeField_(container, licenseHeaderValue, valueSetup, valueOnChange);
+      this.makeField_(container, 'Header Value', valueSetup, valueOnChange);
     };
     if (assetInProgress.licenseRequestHeaders.size == 0) {
       // It starts out with a single empty row, but each time you start filling
@@ -269,8 +260,8 @@ shakaDemo.Custom = class {
     const fullMimeTypeOnChange = (input) => {
       assetInProgress.setMediaPlaylistFullMimeType(input.value);
     };
-    const fullMimeTypeName = shakaDemoMain.getLocalizedString(
-        shakaDemo.MessageIds.HLS_FULL_MIME_TYPE);
+    const fullMimeTypeName =
+        'Full Mime Type for Playing Media Playlists Directly';
     this.makeField_(
         container, fullMimeTypeName, fullMimeTypeSetup, fullMimeTypeOnChange);
 
@@ -300,10 +291,7 @@ shakaDemo.Custom = class {
     const adTagOnChange = (input) => {
       assetInProgress.adTagUri = input.value;
     };
-    const adTagURLName = shakaDemoMain.getLocalizedString(
-        shakaDemo.MessageIds.AD_TAG_URL);
-    this.makeField_(
-        container, adTagURLName, adTagSetup, adTagOnChange);
+    this.makeField_(container, 'Ad Tag URL', adTagSetup, adTagOnChange);
 
     // Make the content source id field.
     const contentSrcIdSetup = (input, container) => {
@@ -319,8 +307,7 @@ shakaDemo.Custom = class {
       this.manifestField_.required =
         this.checkManifestRequired_(assetInProgress);
     };
-    const contentSrcIdName = shakaDemoMain.getLocalizedString(
-        shakaDemo.MessageIds.IMA_CONTENT_SRC_ID);
+    const contentSrcIdName = 'Content source ID (for VOD DAI Content)';
     this.makeField_(
         container, contentSrcIdName, contentSrcIdSetup, contentSrcIdOnChange);
 
@@ -338,10 +325,8 @@ shakaDemo.Custom = class {
       this.manifestField_.required =
         this.checkManifestRequired_(assetInProgress);
     };
-    const videoIdName = shakaDemoMain.getLocalizedString(
-        shakaDemo.MessageIds.IMA_VIDEO_ID);
-    this.makeField_(
-        container, videoIdName, videoIdSetup, videoIdOnChange);
+    const videoIdName = 'Video ID (for VOD DAI Content)';
+    this.makeField_(container, videoIdName, videoIdSetup, videoIdOnChange);
 
     // Make the asset key field.
     const assetKeySetup = (input, container) => {
@@ -357,10 +342,8 @@ shakaDemo.Custom = class {
       this.manifestField_.required =
         this.checkManifestRequired_(assetInProgress);
     };
-    const assetKeyName = shakaDemoMain.getLocalizedString(
-        shakaDemo.MessageIds.IMA_ASSET_KEY);
-    this.makeField_(
-        container, assetKeyName, assetKeySetup, assetKeyChange);
+    const assetKeyName = 'Asset key (for LIVE DAI Content)';
+    this.makeField_(container, assetKeyName, assetKeySetup, assetKeyChange);
 
     // Make the manifest type field.
     const manifestTypeSetup = (input, container) => {
@@ -376,8 +359,7 @@ shakaDemo.Custom = class {
       this.manifestField_.required =
         this.checkManifestRequired_(assetInProgress);
     };
-    const manifestTypeName = shakaDemoMain.getLocalizedString(
-        shakaDemo.MessageIds.IMA_MANIFEST_TYPE);
+    const manifestTypeName = 'Manifest type (for DAI Content)';
     this.makeField_(
         container, manifestTypeName, manifestTypeSetup, manifestTypeChange);
 
@@ -437,10 +419,8 @@ shakaDemo.Custom = class {
     const licenseOnChange = (input) => {
       setLicenseServerURLs();
     };
-    const licenseServerURLName = shakaDemoMain.getLocalizedString(
-        shakaDemo.MessageIds.LICENSE_SERVER_URL);
     this.makeField_(
-        container, licenseServerURLName, licenseSetup, licenseOnChange);
+        container, 'Custom License Server URL', licenseSetup, licenseOnChange);
 
     // Make the license certificate URL field.
     const certSetup = (input, container) => {
@@ -451,10 +431,8 @@ shakaDemo.Custom = class {
     const certOnChange = (input) => {
       assetInProgress.certificateUri = input.value;
     };
-    const licenseCertificateURLName = shakaDemoMain.getLocalizedString(
-        shakaDemo.MessageIds.LICENSE_CERTIFICATE_URL);
     this.makeField_(
-        container, licenseCertificateURLName, certSetup, certOnChange);
+        container, 'Custom License Certificate URL', certSetup, certOnChange);
 
     // Make the drm system field.
     const drmSetup = (input, container) => {
@@ -470,10 +448,7 @@ shakaDemo.Custom = class {
     const drmOnChange = (input) => {
       setLicenseServerURLs();
     };
-    const DRMSystemName = shakaDemoMain.getLocalizedString(
-        shakaDemo.MessageIds.DRM_SYSTEM);
-    this.makeField_(
-        container, DRMSystemName, drmSetup, drmOnChange);
+    this.makeField_(container, 'Custom DRM System', drmSetup, drmOnChange);
 
     return drmDiv;
   }
@@ -508,8 +483,7 @@ shakaDemo.Custom = class {
       // Make an error that shows up if you did not provide valid JSON.
       const error = document.createElement('span');
       error.classList.add('mdl-textfield__error');
-      error.textContent = shakaDemoMain.getLocalizedString(
-          shakaDemo.MessageIds.INVALID_JSON_CONFIG_ERROR);
+      error.textContent = 'Invalid JSON configuration';
 
       container.appendChild(error);
     };
@@ -526,8 +500,7 @@ shakaDemo.Custom = class {
         inputWrapper.setValid(false);
       }
     };
-    const extraConfigLabel = shakaDemoMain.getLocalizedString(
-        shakaDemo.MessageIds.EXTRA_SHAKA_PLAYER_CONFIG);
+    const extraConfigLabel = 'Extra Shaka Player configuration (JSON)';
     this.makeField_(
         container, extraConfigLabel, extraSetup, extraOnChange,
         /* isTextArea= */ true);
@@ -557,8 +530,7 @@ shakaDemo.Custom = class {
       // Make an error that shows up if you did not provide an URL.
       const error = document.createElement('span');
       error.classList.add('mdl-textfield__error');
-      error.textContent = shakaDemoMain.getLocalizedString(
-          shakaDemo.MessageIds.MANIFEST_URL_ERROR);
+      error.textContent = 'Must have a manifest URL, or IMA DAI id fields';
       container.appendChild(error);
 
       // Add a regex that will detect empty strings.
@@ -569,10 +541,7 @@ shakaDemo.Custom = class {
     const manifestOnChange = (input) => {
       assetInProgress.manifestUri = input.value.trim();
     };
-    const manifestURLName = shakaDemoMain.getLocalizedString(
-        shakaDemo.MessageIds.MANIFEST_URL);
-    this.makeField_(
-        container, manifestURLName, manifestSetup, manifestOnChange);
+    this.makeField_(container, 'Manifest URL', manifestSetup, manifestOnChange);
 
     // Make the name field.
     const nameSetup = (input, container) => {
@@ -582,8 +551,7 @@ shakaDemo.Custom = class {
       // Make an error that shows up if you have an empty/duplicate name.
       const error = document.createElement('span');
       error.classList.add('mdl-textfield__error');
-      error.textContent = shakaDemoMain.getLocalizedString(
-          shakaDemo.MessageIds.NAME_ERROR);
+      error.textContent = 'Must be a unique name.';
       container.appendChild(error);
 
       // Make a regex that will detect duplicates.
@@ -604,10 +572,7 @@ shakaDemo.Custom = class {
     const nameOnChange = (input) => {
       assetInProgress.name = input.value;
     };
-    const nameName = shakaDemoMain.getLocalizedString(
-        shakaDemo.MessageIds.NAME);
-    this.makeField_(
-        container, nameName, nameSetup, nameOnChange);
+    this.makeField_(container, 'Name', nameSetup, nameOnChange);
 
     // Make the icon field.
     const iconSetup = (input, container) => {
@@ -634,11 +599,7 @@ shakaDemo.Custom = class {
         iconDiv.appendChild(img);
       }
     };
-
-    const iconURLName = shakaDemoMain.getLocalizedString(
-        shakaDemo.MessageIds.ICON_URL);
-    this.makeField_(
-        container, iconURLName, iconSetup, iconOnChange);
+    this.makeField_(container, 'Icon URL', iconSetup, iconOnChange);
 
     // Make the MIME type field.
     const mimeTypeSetup = (input, container) => {
@@ -650,11 +611,7 @@ shakaDemo.Custom = class {
     const mimeTypeOnChange = (input) => {
       assetInProgress.mimeType = input.value || null;
     };
-
-    const mimeTypeName = shakaDemoMain.getLocalizedString(
-        shakaDemo.MessageIds.MIME_TYPE);
-    this.makeField_(
-        container, mimeTypeName, mimeTypeSetup, mimeTypeOnChange);
+    this.makeField_(container, 'MIME Type', mimeTypeSetup, mimeTypeOnChange);
 
     return mainDiv;
   }
@@ -681,9 +638,7 @@ shakaDemo.Custom = class {
     const finishDiv = document.createElement('tr');
 
     const buttonStyle = shakaDemo.Custom.ButtonStyle_.RAISED;
-    const saveString =
-        shakaDemoMain.getLocalizedString(shakaDemo.MessageIds.SAVE_BUTTON);
-    finishDiv.appendChild(this.makeButton_(saveString, buttonStyle, () => {
+    finishDiv.appendChild(this.makeButton_('Save', buttonStyle, () => {
       for (const input of inputsToCheck) {
         if (!input.validity.valid) {
           return;
@@ -695,9 +650,7 @@ shakaDemo.Custom = class {
       this.remakeSavedList_();
       this.dialog_.close();
     }));
-    const cancelString =
-        shakaDemoMain.getLocalizedString(shakaDemo.MessageIds.CANCEL_BUTTON);
-    finishDiv.appendChild(this.makeButton_(cancelString, buttonStyle, () => {
+    finishDiv.appendChild(this.makeButton_('Cancel', buttonStyle, () => {
       this.dialog_.close();
     }));
 
@@ -737,9 +690,8 @@ shakaDemo.Custom = class {
     const tabDiv = document.createElement('tr');
     const tabsToHide = [];
     const buttonsToSwitch = [];
-    const addTabButton = (messageId, tabToShow, startOn) => {
+    const addTabButton = (name, tabToShow, startOn) => {
       const buttonStyle = shakaDemo.Custom.ButtonStyle_.PLAIN;
-      const name = shakaDemoMain.getLocalizedString(messageId);
       const button = this.makeButton_(name, buttonStyle, () => {
         for (const tab of tabsToHide) {
           tab.classList.add('hidden');
@@ -759,18 +711,12 @@ shakaDemo.Custom = class {
         tabToShow.classList.add('hidden');
       }
     };
-    addTabButton(
-        shakaDemo.MessageIds.MAIN_TAB, mainDiv, /* startOn= */ true);
-    addTabButton(
-        shakaDemo.MessageIds.DRM_TAB, drmDiv, /* startOn= */ false);
-    addTabButton(
-        shakaDemo.MessageIds.HEADERS_TAB, headersDiv, /* startOn= */ false);
-    addTabButton(
-        shakaDemo.MessageIds.ADS_TAB, adsDiv, /* startOn= */ false);
-    addTabButton(
-        shakaDemo.MessageIds.HLS_TAB, hlsDiv, /* startOn= */ false);
-    addTabButton(
-        shakaDemo.MessageIds.EXTRA_TAB, extraConfigDiv, /* startOn= */ false);
+    addTabButton('Main', mainDiv, /* startOn= */ true);
+    addTabButton('Drm', drmDiv, /* startOn= */ false);
+    addTabButton('Headers', headersDiv, /* startOn= */ false);
+    addTabButton('Ads', adsDiv, /* startOn= */ false);
+    addTabButton('HLS', hlsDiv, /* startOn= */ false);
+    addTabButton('Extra Config', extraConfigDiv, /* startOn= */ false);
 
     // Append the divs in the desired order.
     this.dialog_.appendChild(tabDiv);
@@ -861,24 +807,24 @@ shakaDemo.Custom = class {
     const savedList = this.savedList_;
     const isFeatured = false;
     return new shakaDemo.AssetCard(savedList, asset, isFeatured, (c) => {
-      c.addButton(shakaDemo.MessageIds.PLAY, () => {
+      c.addButton('Play', () => {
         shakaDemoMain.loadAsset(asset);
         this.updateSelected_();
       });
-      c.addButton(shakaDemo.MessageIds.EDIT_CUSTOM, async () => {
+      c.addButton('Edit', async () => {
         if (asset.unstoreCallback) {
           await asset.unstoreCallback();
         }
         this.showAssetDialog_(asset);
       });
-      c.addButton(shakaDemo.MessageIds.DELETE_CUSTOM, async () => {
+      c.addButton('Delete', async () => {
         this.assets_.delete(asset);
         if (asset.unstoreCallback) {
           await asset.unstoreCallback();
         }
         this.saveAssetInfos_(this.assets_);
         this.remakeSavedList_();
-      }, shakaDemo.MessageIds.DELETE_CUSTOM);
+      }, 'Delete this custom asset?');
       c.addStoreButton();
     });
   }
@@ -905,15 +851,10 @@ shakaDemo.Custom = class {
         textElement.textContent = text;
         this.savedList_.appendChild(textElement);
       };
-      makeMessage('title',
-          shakaDemoMain.getLocalizedString(
-              shakaDemo.MessageIds.CUSTOM_INTRO_ONE));
-      makeMessage('body-2',
-          shakaDemoMain.getLocalizedString(
-              shakaDemo.MessageIds.CUSTOM_INTRO_TWO));
+      makeMessage('title', 'Try Shaka Player with your own content!');
+      makeMessage('body-2', 'Press the button below to add a custom asset.');
       makeMessage('body-1',
-          shakaDemoMain.getLocalizedString(
-              shakaDemo.MessageIds.CUSTOM_INTRO_THREE));
+          'Custom assets will remain even after reloading the page.');
     } else {
       // Make asset cards for the assets.
       this.assetCards_ = Array.from(this.assets_).map((asset) => {
diff --git a/demo/front.js b/demo/front.js
index dac025b6e..ee7ac4921 100644
--- a/demo/front.js
+++ b/demo/front.js
@@ -9,7 +9,6 @@ goog.provide('shakaDemo.Front');
 
 
 goog.require('shakaDemo.AssetCard');
-goog.require('shakaDemo.MessageIds');
 goog.requireType('ShakaDemoAssetInfo');
 
 /** @type {?shakaDemo.Front} */
@@ -50,9 +49,6 @@ shakaDemo.Front = class {
     document.addEventListener('shaka-main-offline-progress', () => {
       this.updateOfflineProgress_();
     });
-    document.addEventListener('shaka-main-locale-changed', () => {
-      this.remakeAssetCards_();
-    });
     document.addEventListener('shaka-main-page-changed', () => {
       if (!this.assetCardDiv_.childNodes.length &&
           !container.classList.contains('hidden')) {
@@ -74,19 +70,20 @@ shakaDemo.Front = class {
     const makeMessage = (textClass, text) => {
       const textElement = document.createElement('h2');
       textElement.classList.add('mdl-typography--' + textClass);
-      textElement.textContent = shakaDemoMain.getLocalizedString(text);
+      textElement.textContent = text;
       this.messageDiv_.appendChild(textElement);
     };
-    makeMessage('body-2', shakaDemo.MessageIds.FRONT_INTRO_ONE);
-    makeMessage('body-1', shakaDemo.MessageIds.FRONT_INTRO_TWO);
+    makeMessage('body-2', 'This is a demo of Google\'s Shaka Player, a ' +
+        'JavaScript library for adaptive video streaming.');
+    makeMessage('body-1', 'Choose a video to playback; more assets are ' +
+        'available via the "all content" tab.');
 
     const hideButton = document.createElement('button');
     hideButton.classList.add('mdl-button');
     hideButton.classList.add('mdl-button--colored');
     hideButton.classList.add('mdl-js-button');
     hideButton.classList.add('mdl-js-ripple-effect');
-    hideButton.textContent = shakaDemoMain.getLocalizedString(
-        shakaDemo.MessageIds.FRONT_INTRO_DISMISS);
+    hideButton.textContent = 'Dismiss';
     hideButton.addEventListener('click', () => {
       shaka.util.Dom.removeAllChildren(this.messageDiv_);
       window.localStorage.setItem(hideName, 'true');
@@ -122,7 +119,7 @@ shakaDemo.Front = class {
       if (unsupportedReason) {
         c.markAsUnsupported(unsupportedReason);
       } else {
-        c.addButton(shakaDemo.MessageIds.PLAY, () => {
+        c.addButton('Play', () => {
           shakaDemoMain.loadAsset(asset);
           this.updateSelected_();
         });
diff --git a/demo/index.html b/demo/index.html
index b3c670ed3..c929f3fb9 100644
--- a/demo/index.html
+++ b/demo/index.html
@@ -85,7 +85,6 @@ UNCOMPILED_JS = [
   // Enable less, the CSS pre-processor.
   '../node_modules/less/dist/less.js',
   // These are the individual parts of the demo app.
-  'common/message_ids.js',
   'common/asset.js',
   'common/assets.js',
   'demo_uncompiled.js',
@@ -100,11 +99,11 @@ UNCOMPILED_JS = [
       <header class="app-header mdl-layout__header should-hide-in-no-input-mode">
         <header class="mdl-layout__header-row" id="nav-button-container">
           <img alt="Shaka Player Logo" src="shaka_logo_trans.png" class="logo" />
-          <button id="nav-button-front" class="mdl-button mdl-js-button mdl-js-ripple-effect should-disable-on-fail" defaultselected localized-string="HOME" tab-identifier="HOME"></button>
-          <button id="nav-button-search" class="mdl-button mdl-js-button mdl-js-ripple-effect should-disable-on-fail" localized-string="ALL_CONTENT" tab-identifier="ALL_CONTENT"></button>
-          <button id="nav-button-custom" class="mdl-button mdl-js-button mdl-js-ripple-effect should-disable-on-fail" localized-string="CUSTOM_CONTENT" tab-identifier="CUSTOM CONTENT"></button>
+          <button id="nav-button-front" class="mdl-button mdl-js-button mdl-js-ripple-effect should-disable-on-fail" defaultselected tab-identifier="HOME">HOME</button>
+          <button id="nav-button-search" class="mdl-button mdl-js-button mdl-js-ripple-effect should-disable-on-fail" tab-identifier="ALL_CONTENT">ALL CONTENT</button>
+          <button id="nav-button-custom" class="mdl-button mdl-js-button mdl-js-ripple-effect should-disable-on-fail" tab-identifier="CUSTOM CONTENT">CUSTOM CONTENT</button>
           <div class="mdl-layout-spacer"></div>
-          <button id="bug-button" class="mdl-button mdl-js-button mdl-js-ripple-effect should-disable-on-fail" localized-string="REPORT_BUG"></button>
+          <button id="bug-button" class="mdl-button mdl-js-button mdl-js-ripple-effect should-disable-on-fail">REPORT BUG</button>
           <div class="version-block">
             <span class="version-string"></span>
           </div>
@@ -115,7 +114,7 @@ UNCOMPILED_JS = [
       </div>
       <div class="mdl-layout__drawer hamburger-menu">
         <div id="hamburger-menu-title" class="mdl-layout-title">
-          <div localized-string="CONFIG"></div>
+          <div>Shaka Player Demo Config</div>
           <div class="mdl-layout-spacer"></div>
           <button id="drawer-close-button" class="mdl-button mdl-js-button mdl-button--icon should-disable-on-fail"><i class="material-icons-round">close</i></button>
         </div>
@@ -142,28 +141,28 @@ UNCOMPILED_JS = [
           <div class="mdl-mega-footer__middle-section">
 
             <div class="mdl-mega-footer__drop-down-section">
-              <h1 class="mdl-mega-footer__heading" localized-string="PROJECT_LINKS_HEADER"></h1>
+              <h1 class="mdl-mega-footer__heading">PROJECT LINKS</h1>
               <ul class="mdl-mega-footer__link-list">
-                <li><a rel="noopener" target="_blank" href="../docs/api/index.html" localized-string="DOCUMENTATION"></a></li>
-                <li><a rel="noopener" target="_blank" href="https://www.apache.org/licenses/LICENSE-2.0" localized-string="LICENSE"></a></li>
-                <li><a rel="noopener" target="_blank" href="https://github.com/shaka-project/shaka-player" localized-string="SOURCE"></a></li>
-                <li><a rel="noopener" target="_blank" href="https://www.npmjs.com/package/shaka-player" localized-string="NPM"></a></li>
-                <li><a rel="noopener" target="_blank" href="../support.html" localized-string="SUPPORT"></a></li>
+                <li><a rel="noopener" target="_blank" href="../docs/api/index.html">Documentation</a></li>
+                <li><a rel="noopener" target="_blank" href="https://www.apache.org/licenses/LICENSE-2.0">Apache License</a></li>
+                <li><a rel="noopener" target="_blank" href="https://github.com/shaka-project/shaka-player">Source on GitHub</a></li>
+                <li><a rel="noopener" target="_blank" href="https://www.npmjs.com/package/shaka-player">Package on NPM</a></li>
+                <li><a rel="noopener" target="_blank" href="../support.html">Browser Support Test</a></li>
               </ul>
             </div>
             <div class="mdl-mega-footer__drop-down-section">
-              <h1 class="mdl-mega-footer__heading" localized-string="CDN_HEADER"></h1>
+              <h1 class="mdl-mega-footer__heading">CDN</h1>
               <ul class="mdl-mega-footer__link-list">
-                <li><a rel="noopener" target="_blank" href="https://developers.google.com/speed/libraries/#shaka-player" localized-string="LIBRARIES"></a></li>
-                <li><a rel="noopener" target="_blank" href="https://www.jsdelivr.com/package/npm/shaka-player" localized-string="JSDELIVR"></a></li>
+                <li><a rel="noopener" target="_blank" href="https://developers.google.com/speed/libraries/#shaka-player">Google Hosted Libraries</a></li>
+                <li><a rel="noopener" target="_blank" href="https://www.jsdelivr.com/package/npm/shaka-player">jsDelivr</a></li>
               </ul>
             </div>
             <div class="mdl-mega-footer__drop-down-section">
-              <h1 class="mdl-mega-footer__heading" localized-string="DEMO_MODE_HEADER"></h1>
+              <h1 class="mdl-mega-footer__heading">DEMO MODE</h1>
               <ul class="mdl-mega-footer__link-list" id="compiled-links">
-                <li><a href="#build=compiled" id="compiled-link" localized-string="COMPILED_RELEASE"></a></li>
-                <li><a href="#build=debug_compiled" id="debug-compiled-link" localized-string="COMPILED_DEBUG"></a></li>
-                <li><a href="#build=uncompiled" id="uncompiled-link" localized-string="UNCOMPILED"></a></li>
+                <li><a href="#build=compiled" id="compiled-link">Compiled (Release)</a></li>
+                <li><a href="#build=debug_compiled" id="debug-compiled-link">Compiled (Debug)</a></li>
+                <li><a href="#build=uncompiled" id="uncompiled-link">Uncompiled</a></li>
               </ul>
             </div>
           </div>
diff --git a/demo/input.js b/demo/input.js
index 448617bf0..5ac435ae7 100644
--- a/demo/input.js
+++ b/demo/input.js
@@ -11,7 +11,6 @@ goog.provide('shakaDemo.NumberInput');
 goog.provide('shakaDemo.SelectInput');
 goog.provide('shakaDemo.TextInput');
 
-goog.require('shakaDemo.MessageIds');
 goog.requireType('shakaDemo.InputContainer');
 
 /**
@@ -121,7 +120,7 @@ shakaDemo.Input.lastId_ = 0;
 shakaDemo.SelectInput = class extends shakaDemo.Input {
   /**
    * @param {!shakaDemo.InputContainer} parentContainer
-   * @param {?shakaDemo.MessageIds} name
+   * @param {?string} name
    * @param {function(!HTMLInputElement, !shakaDemo.Input)} onChange
    * @param {!Object.<string, string>} values
    */
@@ -134,7 +133,7 @@ shakaDemo.SelectInput = class extends shakaDemo.Input {
     this.extra_.classList.add('mdl-textfield__label');
     this.extra_.setAttribute('for', this.input_.id);
     if (name) {
-      this.extra_.textContent = shakaDemoMain.getLocalizedString(name);
+      this.extra_.textContent = name;
     }
     for (const value of Object.keys(values)) {
       const option =
@@ -243,18 +242,14 @@ shakaDemo.NumberInput = class extends shakaDemo.TextInput {
     error.classList.add('mdl-textfield__error');
     this.container_.appendChild(error);
 
-    const MessageIds = shakaDemo.MessageIds;
-    const localize = (name) => shakaDemoMain.getLocalizedString(name);
     if (canBeZero && canBeDecimal) {
-      error.textContent = localize(MessageIds.NUMBER_DECIMAL_WARNING);
+      error.textContent = 'Must be a positive number.';
     } else if (canBeZero) {
-      error.textContent = localize(MessageIds.NUMBER_INTEGER_WARNING);
+      error.textContent = 'Must be a positive integer.';
     } else if (canBeDecimal) {
-      error.textContent =
-          localize(MessageIds.NUMBER_NONZERO_DECIMAL_WARNING);
+      error.textContent = 'Must be a positive, nonzero number.';
     } else {
-      error.textContent =
-          localize(MessageIds.NUMBER_NONZERO_INTEGER_WARNING);
+      error.textContent = 'Must be a positive, nonzero integer.';
     }
 
     this.input_.pattern = '(Infinity|';
diff --git a/demo/input_container.js b/demo/input_container.js
index 0637493f5..5db22b1cf 100644
--- a/demo/input_container.js
+++ b/demo/input_container.js
@@ -9,7 +9,6 @@ goog.provide('shakaDemo.InputContainer');
 
 
 goog.require('shakaDemo.Tooltips');
-goog.requireType('shakaDemo.MessageIds');
 
 /**
  * Creates elements for containing inputs. It represents a single "section" of
@@ -22,8 +21,8 @@ goog.requireType('shakaDemo.MessageIds');
 shakaDemo.InputContainer = class {
   /**
    * @param {!Element} parentDiv
-   * @param {?shakaDemo.MessageIds} headerText The text to be displayed by
-   *   the header. If null, there will be no header.
+   * @param {?string} headerText The text to be displayed by the header.
+   *   If null, there will be no header.
    * @param {!shakaDemo.InputContainer.Style} style
    * @param {?string} docLink
    */
@@ -46,7 +45,7 @@ shakaDemo.InputContainer = class {
     /** @type {?Element} */
     this.latestElementContainer;
 
-    /** @type {?shakaDemo.MessageIds} */
+    /** @type {?string} */
     this.latestTooltip;
 
     /** @private {number} */
@@ -101,7 +100,7 @@ shakaDemo.InputContainer = class {
 
   /**
    * @param {!Element} parentDiv
-   * @param {shakaDemo.MessageIds} headerText
+   * @param {string} headerText
    * @private
    */
   createHeader_(parentDiv, headerText) {
@@ -123,7 +122,7 @@ shakaDemo.InputContainer = class {
       this.header_ = document.createElement('div');
       this.header_.classList.add('input-header');
     }
-    this.header_.textContent = shakaDemoMain.getLocalizedString(headerText);
+    this.header_.textContent = headerText;
     parentDiv.appendChild(this.header_);
   }
 
@@ -170,8 +169,8 @@ shakaDemo.InputContainer = class {
 
   /**
    * Makes a row, for storing an input.
-   * @param {?shakaDemo.MessageIds} labelString
-   * @param {?shakaDemo.MessageIds} tooltipString
+   * @param {?string} labelString
+   * @param {?string} tooltipString
    * @param {string=} rowClass
    */
   addRow(labelString, tooltipString, rowClass) {
@@ -190,7 +189,7 @@ shakaDemo.InputContainer = class {
       label.setAttribute('for', elementId);
       label.classList.add('input-container-label');
       const labelText = document.createElement('b');
-      labelText.textContent = shakaDemoMain.getLocalizedString(labelString);
+      labelText.textContent = labelString;
       label.appendChild(labelText);
       this.latestRow_.appendChild(label);
     }
diff --git a/demo/locales/en.json b/demo/locales/en.json
deleted file mode 100644
index 4bce0b7ff..000000000
--- a/demo/locales/en.json
+++ /dev/null
@@ -1,289 +0,0 @@
-{
-  "DEMO_ADAPTATION_RESTRICTIONS_SECTION_HEADER": "Adaptation Restrictions",
-  "DEMO_ADAPTATION_SECTION_HEADER": "Adaptation",
-  "DEMO_ADS": "Ads",
-  "DEMO_AD_SEARCH": "Filters for assets that have advertisements.",
-  "DEMO_AD_TAG_URL": "Ad Tag URL",
-  "DEMO_ADS_TAB": "Ads",
-  "DEMO_ADS_SECTION_HEADER": "Ads",
-  "DEMO_AES128": "AES-128 protection",
-  "DEMO_ALL_CONTENT": "ALL CONTENT",
-  "DEMO_ALWAYS_STREAM_TEXT": "Always Stream Text",
-  "DEMO_ALWAYS_STREAM_TEXT_WARNING": "Text must always be streamed while native controls are enabled, for captions to work.",
-  "DEMO_APPLE": "Apple",
-  "DEMO_AUDIO_CHANNEL_COUNT": "Preferred Audio Channel Count",
-  "DEMO_AUDIO_LANGUAGE": "Preferred Audio Language",
-  "DEMO_AUDIO_LABEL": "Preferred Audio Label",
-  "DEMO_AUDIO_ONLY": "Audio only",
-  "DEMO_AUDIO_ONLY_SEARCH": "Filters for assets that do not have video streams.",
-  "DEMO_AUDIO_ROBUSTNESS": "Audio Robustness",
-  "DEMO_AUTO_CORRECT_DASH_DRIFT": "Auto-Correct DASH Drift",
-  "DEMO_AUTO_LOW_LATENCY": "Auto Low Latency Mode",
-  "DEMO_AUTO_SHOW_TEXT": "Auto-Show Text",
-  "DEMO_AUTO_SHOW_TEXT_NEVER": "Never",
-  "DEMO_AUTO_SHOW_TEXT_ALWAYS": "Always",
-  "DEMO_AUTO_SHOW_TEXT_IF_PREFERRED_TEXT_LANGUAGE": "If preferred text language",
-  "DEMO_AUTO_SHOW_TEXT_IF_SUBTITLES_MAY_BE_NEEDED": "If subtitles may be needed",
-  "DEMO_AVAILABILITY_WINDOW_OVERRIDE": "Availability Window Override",
-  "DEMO_AXINOM": "Axinom",
-  "DEMO_AZURE_MEDIA_SERVICES": "Azure Media Services",
-  "DEMO_BACKOFF_FACTOR": "Backoff Factor",
-  "DEMO_BANDWIDTH_DOWNGRADE": "Bandwidth Downgrade Target",
-  "DEMO_BANDWIDTH_ESTIMATE": "Default Bandwidth Estimate",
-  "DEMO_BANDWIDTH_UPGRADE": "Bandwidth Upgrade Target",
-  "DEMO_BASE_DELAY": "Base Delay",
-  "DEMO_BITCODIN": "Bitcodin",
-  "DEMO_BUFFERING_GOAL": "Buffering Goal",
-  "DEMO_BUFFER_BEHIND": "Buffer Behind",
-  "DEMO_CANCEL_BUTTON": "Cancel",
-  "DEMO_CAPTIONS": "Captions",
-  "DEMO_CDN_HEADER": "CDN",
-  "DEMO_CLEAR": "No DRM protection",
-  "DEMO_CLEAR_KEY": "Clear Key DRM",
-  "DEMO_CLOCK_SYNC_URI": "Clock Sync URI",
-  "DEMO_CLEAR_BUFFER_SWITCH": "Clear video buffer on abr rendition switch",
-  "DEMO_CMCD_SECTION_HEADER": "CMCD",
-  "DEMO_COMPILED_DEBUG": "Compiled (Debug)",
-  "DEMO_COMPILED_RELEASE": "Compiled (Release)",
-  "DEMO_CONNECTION_TIMEOUT": "Connection timeout",
-  "DEMO_CONFIG": "Shaka Player Demo Config",
-  "DEMO_CONTAINER_SEARCH": "Container",
-  "DEMO_CONTAINERLESS": "Containerless",
-  "DEMO_CONTENT_ID": "Content ID",
-  "DEMO_CUSTOM": "Custom",
-  "DEMO_CUSTOM_CONTENT": "CUSTOM CONTENT",
-  "DEMO_CUSTOM_INTRO_ONE": "Try Shaka Player with your own content!",
-  "DEMO_CUSTOM_INTRO_THREE": "Custom assets will remain even after reloading the page.",
-  "DEMO_CUSTOM_INTRO_TWO": "Press the button below to add a custom asset.",
-  "DEMO_CUSTOM_PLAYHEAD_TRACKER": "Custom playhead tracker",
-  "DEMO_DASH": "DASH",
-  "DEMO_DASH_IF": "DASH-IF",
-  "DEMO_DASH_SEQUENCE_MODE": "Enable DASH sequence mode",
-  "DEMO_DEFAULT_AUDIO_CODEC": "Default Audio Codec",
-  "DEMO_DEFAULT_PRESENTATION_DELAY": "Default Presentation Delay",
-  "DEMO_DEFAULT_VIDEO_CODEC": "Default Video Codec",
-  "DEMO_DELAY_LICENSE": "Delay License Request Until Played",
-  "DEMO_DELETE_CUSTOM": "Delete",
-  "DEMO_DELETE_CUSTOM_PROMPT": "Delete this custom asset?",
-  "DEMO_DELETE_STORED_PROMPT": "Delete the offline copy?",
-  "DEMO_DEMO_MODE_HEADER": "DEMO MODE",
-  "DEMO_DISABLE_AUDIO": "Disable Audio",
-  "DEMO_DISABLE_TEXT": "Disable Text",
-  "DEMO_DISABLE_THUMBNAILS": "Disable Thumbnails",
-  "DEMO_DISABLE_VIDEO": "Disable Video",
-  "DEMO_DISABLE_XLINK_PROCESSING": "Disable Xlink processing",
-  "DEMO_DISPATCH_ALL_EMSG_BOXES": "Dispatch all emsg boxes",
-  "DEMO_DOCUMENTATION": "Documentation",
-  "DEMO_DRM_RETRY_SECTION_HEADER": "DRM Retry Parameters",
-  "DEMO_DRM_SEARCH": "DRM",
-  "DEMO_DRM_SECTION_HEADER": "DRM",
-  "DEMO_DRM_SYSTEM": "Custom DRM System",
-  "DEMO_DRM_TAB": "Drm",
-  "DEMO_DRM_SESSION_TYPE": "Session Type",
-  "DEMO_DURATION_BACKOFF": "Duration Backoff",
-  "DEMO_EDIT_CUSTOM": "Edit",
-  "DEMO_ENABLED": "Enabled",
-  "DEMO_ENABLE_AUDIO_GROUPS": "Enable Audio Groups",
-  "DEMO_EXTRA_SHAKA_PLAYER_CONFIG": "Extra Shaka Player configuration (JSON)",
-  "DEMO_EXTRA_TAB": "Extra Config",
-  "DEMO_FAIRPLAY": "Fairplay DRM",
-  "DEMO_FAST_HALF_LIFE": "Fast half life",
-  "DEMO_FORCE_HTTPS": "Force HTTPS",
-  "DEMO_FORCE_TRANSMUX": "Force Transmux",
-  "DEMO_INSERT_FAKE_ENCRYPTION_IN_INIT": "Insert fake encryption in init segments when needed by the platform.",
-  "DEMO_FRONT_INTRO_DISMISS": "Dismiss",
-  "DEMO_FRONT_INTRO_ONE": "This is a demo of Google's Shaka Player, a JavaScript library for adaptive video streaming.",
-  "DEMO_FRONT_INTRO_TWO": "Choose a video to playback; more assets are available via the \"all content\" tab.",
-  "DEMO_FUZZ_FACTOR": "Fuzz Factor",
-  "DEMO_GAP_DETECTION_THRESHOLD": "Gap detection threshold",
-  "DEMO_GAP_JUMP_TIMER_TIME": "Gap jump timer time",
-  "DEMO_GPAC": "GPAC",
-  "DEMO_HEADERS_TAB": "Headers",
-  "DEMO_HDR_LEVEL": "Preferred HDR Level",
-  "DEMO_HDR_LEVEL_AUTO": "Auto Detect",
-  "DEMO_HDR_LEVEL_HLG": "HLG",
-  "DEMO_HDR_LEVEL_NONE": "No Preference",
-  "DEMO_HDR_LEVEL_PQ": "PQ",
-  "DEMO_HDR_LEVEL_SDR": "SDR",
-  "DEMO_HIGH_DEFINITION": "High definition",
-  "DEMO_HIGH_DEFINITION_SEARCH": "Filters for assets with at least one high-definition video stream.",
-  "DEMO_HLS": "HLS",
-  "DEMO_HLS_TAB": "HLS",
-  "DEMO_HOME": "HOME",
-  "DEMO_ICON_URL": "Icon URL",
-  "DEMO_IGNORE_DASH_DRM": "Ignore DASH DRM Info",
-  "DEMO_IGNORE_DASH_EMPTY_ADAPTATION_SET": "Ignore empty DASH AdaptationSets",
-  "DEMO_IGNORE_DASH_MAX_SEGMENT_DURATION": "Ignore DASH maxSegmentDuration",
-  "DEMO_IGNORE_DASH_SUGGESTED_PRESENTATION_DELAY": "Ignore DASH suggestedPresentationDelay",
-  "DEMO_IGNORE_DEVICE_PIXEL_RATIO": "Ignore device pixel ratio",
-  "DEMO_IGNORE_HLS_IMAGE_FAILURES": "Ignore HLS Image Stream Failures",
-  "DEMO_IGNORE_HLS_TEXT_FAILURES": "Ignore HLS Text Stream Failures",
-  "DEMO_IMA_ASSET_KEY": "Asset key (for LIVE DAI Content)",
-  "DEMO_IMA_CONTENT_SRC_ID": "Content source ID (for VOD DAI Content)",
-  "DEMO_IMA_MANIFEST_TYPE": "Manifest type (for DAI Content)",
-  "DEMO_IMA_VIDEO_ID": "Video ID (for VOD DAI Content)",
-  "DEMO_IGNORE_MANIFEST_PROGRAM_DATE_TIME": "Ignore Program Date Time from manifest",
-  "DEMO_IGNORE_MANIFEST_TIMESTAMPS_IN_SEGMENTS_MODE": "Ignore Manifest Timestamps in Segments Mode",
-  "DEMO_IGNORE_MIN_BUFFER_TIME": "Ignore Min Buffer Time",
-  "DEMO_IGNORE_TEXT_FAILURES": "Ignore Text Stream Failures",
-  "DEMO_INACCURATE_MANIFEST_TOLERANCE": "Inaccurate Manifest Tolerance",
-  "DEMO_INITIAL_SEGMENT_LIMIT": "Initial Segment Limit",
-  "DEMO_INVALID_JSON_CONFIG_ERROR": "Invalid JSON configuration",
-  "DEMO_IRT": "IRT",
-  "DEMO_JSDELIVR": "jsDelivr",
-  "DEMO_LANGUAGE_SECTION_HEADER": "Language",
-  "DEMO_LCEVC": "LCEVC",
-  "DEMO_LCEVC_DRAW_LOGO": "Draw LCEVC Logo",
-  "DEMO_LCEVC_DYNAMIC_PERFORMANCE_SCALING": "LCEVC Dynamic Performance scaling",
-  "DEMO_LCEVC_LOG_LEVEL": "LCEVC Log Level",
-  "DEMO_LCEVC_SECTION_HEADER": "MPEG-5 Part-2 LCEVC",
-  "DEMO_LOW_LATENCY_STREAM": "Low Latency Streams",
-  "DEMO_LIBRARIES": "Google Hosted Libraries",
-  "DEMO_LICENSE": "Apache License",
-  "DEMO_LICENSE_CERTIFICATE_URL": "Custom License Certificate URL",
-  "DEMO_LICENSE_HEADER_NAME": "Header Name",
-  "DEMO_LICENSE_HEADER_TITLE": "License Header",
-  "DEMO_LICENSE_HEADER_VALUE": "Header Value",
-  "DEMO_LICENSE_SERVER_URL": "Custom License Server URL",
-  "DEMO_LIVE": "Live",
-  "DEMO_LIVE_SEARCH": "Live",
-  "DEMO_LIVE_SEGMENTS_DELAY": "Live segments delay",
-  "DEMO_LIVE_SYNC": "Live sync",
-  "DEMO_LIVE_SYNC_MAX_LATENCY":"Max latency for live sync",
-  "DEMO_LIVE_SYNC_PLAYBACK_RATE":"Playback rate for live sync",
-  "DEMO_LOG_LEVEL": "Log Level",
-  "DEMO_LOG_LEVEL_DEBUG": "Debug",
-  "DEMO_LOG_LEVEL_INFO": "Info",
-  "DEMO_LOG_LEVEL_V": "Verbose",
-  "DEMO_LOG_LEVEL_VV": "Very Verbose",
-  "DEMO_LOG_LICENSE_EXCHANGE": "Log license exchange data",
-  "DEMO_LOW_LATENCY": "Low Latency Mode",
-  "DEMO_MAIN_TAB": "Main",
-  "DEMO_MANIFEST_RETRY_SECTION_HEADER": "Manifest Retry Parameters",
-  "DEMO_MANIFEST_SEARCH": "Manifest",
-  "DEMO_MANIFEST_SECTION_HEADER": "Manifest",
-  "DEMO_MANIFEST_URL": "Manifest URL",
-  "DEMO_MANIFEST_URL_ERROR": "Must have a manifest URL, or IMA DAI id fields",
-  "DEMO_MAX_ATTEMPTS": "Max Attempts",
-  "DEMO_MAX_BANDWIDTH": "Max Bandwidth",
-  "DEMO_MAX_DISABLED_TIME": "Max Variant Disabled Time",
-  "DEMO_MAX_FRAMERATE": "Max Framerate",
-  "DEMO_MAX_HEIGHT": "Max Height",
-  "DEMO_MAX_PIXELS": "Max Pixels",
-  "DEMO_MAX_WIDTH": "Max Width",
-  "DEMO_MEDIA_SOURCE_SECTION_HEADER": "Media source",
-  "DEMO_METACDN": "MetaCDN",
-  "DEMO_MICROSOFT": "Microsoft",
-  "DEMO_MIME_TYPE": "MIME Type",
-  "DEMO_MIN_BANDWIDTH": "Min Bandwidth",
-  "DEMO_MIN_BYTES": "Min Bytes",
-  "DEMO_MIN_HDCP_VERSION": "Min HDCP version",
-  "DEMO_MIN_FRAMERATE": "Min Framerate",
-  "DEMO_MIN_HEIGHT": "Min Height",
-  "DEMO_MIN_PIXELS": "Min Pixels",
-  "DEMO_MIN_TOTAL_BYTES": "Min total Bytes",
-  "DEMO_MIN_WIDTH": "Min Width",
-  "DEMO_MP2TS": "MPEG-2 TS",
-  "DEMO_MP4": "MP4",
-  "DEMO_MSS": "MSS",
-  "DEMO_MSS_SEQUENCE_MODE": "Enable MSS sequence mode",
-  "DEMO_MULTIPLE_LANGUAGES": "Multiple languages",
-  "DEMO_NAME": "Name",
-  "DEMO_NAME_ERROR": "Must be a unique name.",
-  "DEMO_NETWORK_INFORMATION": "Use Network Information API",
-  "DEMO_NIMBLE_STREAMER": "Nimble Streamer",
-  "DEMO_NPM": "Package on NPM",
-  "DEMO_NUMBER_DECIMAL_WARNING": "Must be a positive number.",
-  "DEMO_NUMBER_INTEGER_WARNING": "Must be a positive integer.",
-  "DEMO_NUMBER_NONZERO_DECIMAL_WARNING": "Must be a positive, nonzero number.",
-  "DEMO_NUMBER_NONZERO_INTEGER_WARNING": "Must be a positive, nonzero integer.",
-  "DEMO_NUMBER_OF_PARALLEL_DOWNLOADS": "Number of parallel downloads",
-  "DEMO_OBSERVE_QUALITY_CHANGES": "Observe media quality changes",
-  "DEMO_PARSE_INBAND_PSSH_ENABLED": "Parse inband 'pssh' from media segments",
-  "DEMO_OFFLINE": "Downloadable",
-  "DEMO_OFFLINE_SEARCH": "Filters for assets that can be stored offline.",
-  "DEMO_OFFLINE_SECTION_HEADER": "Offline",
-  "DEMO_FAILURE_MISC": "Shaka Player failed to load! If you are using an ad blocker, try switching to compiled mode at the bottom of the page.",
-  "DEMO_FAILURE_NO_BROWSER_SUPPORT": "Your browser is not supported!",
-  "DEMO_HLS_FULL_MIME_TYPE": "Full Mime Type for Playing Media Playlists Directly",
-  "DEMO_HLS_SEQUENCE_MODE": "Enable HLS sequence mode",
-  "DEMO_PLAY": "Play",
-  "DEMO_PLAYREADY": "PlayReady DRM",
-  "DEMO_PREFER_FORCED_SUBS": "Prefer Forced Subs",
-  "DEMO_PREFER_NATIVE_HLS": "Prefer native HLS playback when available",
-  "DEMO_PROJECT_LINKS_HEADER": "PROJECT LINKS",
-  "DEMO_PROMPT_NO": "No",
-  "DEMO_PROMPT_YES": "Yes",
-  "DEMO_REBUFFERING_GOAL": "Rebuffering Goal",
-  "DEMO_REPORT_BUG": "REPORT BUG",
-  "DEMO_RESTRICT_TO_ELEMENT_SIZE": "Restrict to element size",
-  "DEMO_RESTRICT_TO_SCREEN_SIZE": "Restrict to screen size",
-  "DEMO_RESTRICTIONS_SECTION_HEADER": "Restrictions",
-  "DEMO_SAFE_MARGIN_SWITCH": "Safe margin on abr switch rendition",
-  "DEMO_SAFE_SEEK_OFFSET": "Safe Seek Offset",
-  "DEMO_SAFE_SKIP_DISTANCE": "Safe Skip Distance",
-  "DEMO_SEGMENT_RELATIVE_VTT_TIMING": "Enable segment-relative VTT Timing",
-  "DEMO_SESSION_ID": "Session ID",
-  "DEMO_SAVE_BUTTON": "Save",
-  "DEMO_SHAKA": "Shaka",
-  "DEMO_SHAKA_CONTROLS": "Shaka Controls",
-  "DEMO_SLOW_HALF_LIFE": "Slow half life",
-  "DEMO_SOURCE": "Source on GitHub",
-  "DEMO_SOURCE_BUFFER_EXTRA_FEATURES": "Source buffer extra features",
-  "DEMO_SOURCE_SEARCH": "Source",
-  "DEMO_STALL_DETECTOR_ENABLED": "Stall Detector Enabled",
-  "DEMO_STALL_THRESHOLD": "Stall Threshold",
-  "DEMO_STALL_TIMEOUT": "Stall timeout",
-  "DEMO_START_AT_SEGMENT_BOUNDARY": "Start At Segment Boundary",
-  "DEMO_STORED": "Downloaded",
-  "DEMO_STORED_SEARCH": "Filters for assets that have been stored offline.",
-  "DEMO_STREAMING_RETRY_SECTION_HEADER": "Streaming Retry Parameters",
-  "DEMO_STREAMING_SECTION_HEADER": "Streaming",
-  "DEMO_SUBTITLES": "Subtitles",
-  "DEMO_SUBTITLES_SEARCH": "Filters for assets with caption tracks, or embedded captions.",
-  "DEMO_SUPPORT": "Browser Support Test",
-  "DEMO_SURROUND": "Surround sound",
-  "DEMO_SURROUND_SEARCH": "Filters for assets with at least one surround sound audio track.",
-  "DEMO_SWITCH_INTERVAL": "Switch Interval",
-  "DEMO_TEXT_LANGUAGE": "Preferred Text Language",
-  "DEMO_TEXT_ROLE": "Preferred Text Role",
-  "DEMO_THUMBNAILS": "Thumbnails",
-  "DEMO_TIMEOUT": "Timeout Factor",
-  "DEMO_TRICK_MODE": "Special trick mode track",
-  "DEMO_TRICK_MODE_SEARCH": "Filters for assets that have special video tracks to be used in trick mode playback (aka fast-forward).",
-  "DEMO_TRICK_PLAY_CONTROLS": "Enabled Trick Play Controls",
-  "DEMO_TRICK_PLAY_CONTROLS_WARNING": "Trick Play controls require the Shaka UI.",
-  "DEMO_UI_LOCALE": "Preferred UI Locale",
-  "DEMO_ULTRA_HIGH_DEFINITION": "Ultra-high definition",
-  "DEMO_UNCOMPILED": "Uncompiled",
-  "DEMO_UNIFIED_STREAMING": "Unified Streaming",
-  "DEMO_UNSUPPORTED": "Not Available",
-  "DEMO_UNSUPPORTED_DISABLED": "This asset is disabled.",
-  "DEMO_UNSUPPORTED_NO_DASH_SUPPORT": "Your browser does not support MPEG-DASH manifests.",
-  "DEMO_UNSUPPORTED_NO_DOWNLOAD": "This asset cannot be downloaded.",
-  "DEMO_UNSUPPORTED_NO_FORMAT_SUPPORT": "Your browser does not support the required video format.",
-  "DEMO_UNSUPPORTED_NO_HLS_SUPPORT": "Your browser does not support HLS manifests.",
-  "DEMO_UNSUPPORTED_NO_KEY_SUPPORT": "Your browser does not support the required key systems.",
-  "DEMO_UNSUPPORTED_NO_LICENSE_SUPPORT": "Your browser does not support offline licenses for the required key systems.",
-  "DEMO_UNSUPPORTED_NO_MSS_SUPPORT": "Your browser does not support MSS manifests.",
-  "DEMO_UNSUPPORTED_NO_OFFLINE": "Your browser does not support offline storage.",
-  "DEMO_UPDATE_EXPIRATION_TIME": "Update expiration time",
-  "DEMO_UPDATE_INTERVAL_SECONDS": "Update interval seconds",
-  "DEMO_UPLYNK": "Verizon Digital Media Services",
-  "DEMO_USE_HEADERS": "Use Headers",
-  "DEMO_USE_NATIVE_HLS_SAFARI": "Use native HLS on Safari",
-  "DEMO_USE_PERSISTENT_LICENSES": "Use Persistent Licenses",
-  "DEMO_USE_SAFARI_BEHAVIOR_FOR_LIVE": "Use Safari behavior for live",
-  "DEMO_VIDEO_ROBUSTNESS": "Video Robustness",
-  "DEMO_VISUALIZER_AUTO_SCREENSHOT_TOGGLE": "Take Screenshot On Stall",
-  "DEMO_VISUALIZER_BUTTON": "Buffer Visualizer",
-  "DEMO_VISUALIZER_SCREENSHOT_BUTTON": "Take Screenshot",
-  "DEMO_VNOVA": "V-Nova",
-  "DEMO_VOD": "VOD",
-  "DEMO_WEBM": "WebM",
-  "DEMO_WIDEVINE": "Widevine DRM",
-  "DEMO_XLINK": "XLink",
-  "DEMO_XLINK_FAIL_GRACEFULLY": "Xlink Should Fail Gracefully",
-  "DEMO_XLINK_SEARCH": "Filters for assets that have XLINK tags in their manifests, so that they can be broken into multiple files.",
-  "DEMO_SEGMENT_PREFETCH_LIMIT": "Segment Prefetch Limit"
-}
diff --git a/demo/locales/source.json b/demo/locales/source.json
deleted file mode 100644
index a607a5035..000000000
--- a/demo/locales/source.json
+++ /dev/null
@@ -1,1150 +0,0 @@
-{
-  "DEMO_ADAPTATION_RESTRICTIONS_SECTION_HEADER": {
-    "description": "The header for a section of configuration values.",
-    "message": "Adaptation Restrictions"
-  },
-  "DEMO_ADAPTATION_SECTION_HEADER": {
-    "description": "The header for a section of configuration values.",
-    "message": "Adaptation"
-  },
-  "DEMO_ADS": {
-    "description": "A tag that marks an asset as having one or more advertisements.",
-    "message": "Ads"
-  },
-  "DEMO_ADS_TAB": {
-    "description": "The header for a tab within the custom asset creation dialog.",
-    "message": "Ads"
-  },
-  "DEMO_ADS_SECTION_HEADER": {
-    "description": "The header for a section of configuration values.",
-    "message": "Ads"
-  },
-  "DEMO_AD_SEARCH": {
-    "description": "A tooltip for an optional search term.",
-    "message": "Filters for assets that have advertisements."
-  },
-  "DEMO_AD_TAG_URL": {
-    "description": "The label on a field that allows users to provide a Ad Tag URL for a custom asset.",
-    "message": "Ad Tag URL"
-  },
-  "DEMO_AES128": {
-    "description": "Text that describes an asset that is not protected with any Digital Rights Management system but it is protected with AES-128.",
-    "message": "[JARGON:AES-128] protection"
-  },
-  "DEMO_ALL_CONTENT": {
-    "description": "A link in the header, that switches to a page for browsing or searching through the entire content library.",
-    "message": "ALL CONTENT"
-  },
-  "DEMO_ALWAYS_STREAM_TEXT": {
-    "description": "The name of a configuration value.",
-    "message": "Always Stream Text"
-  },
-  "DEMO_ALWAYS_STREAM_TEXT_WARNING": {
-    "description": "A tooltip that warns the user that a certain combination of config values cannot be picked.",
-    "message": "Text must always be streamed while native controls are enabled, for captions to work."
-  },
-  "DEMO_APPLE": {
-    "description": "Text that describes an asset that comes from the Apple asset library.",
-    "message": "[PROPER_NAME:Apple]"
-  },
-  "DEMO_AUDIO_CHANNEL_COUNT": {
-    "description": "The name of a configuration value.",
-    "message": "Preferred Audio Channel Count"
-  },
-  "DEMO_AUDIO_LANGUAGE": {
-    "description": "The name of a configuration value.",
-    "message": "Preferred Audio Language"
-  },
-  "DEMO_AUDIO_LABEL": {
-    "description": "The name of a configuration value.",
-    "message": "Preferred Audio Label"
-  },
-  "DEMO_AUDIO_ONLY": {
-    "description": "A tag that marks an asset as having multiple languages.",
-    "message": "Audio only"
-  },
-  "DEMO_AUDIO_ONLY_SEARCH": {
-    "description": "A tooltip for an optional search term.",
-    "message": "Filters for assets that do not have video streams."
-  },
-  "DEMO_AUDIO_ROBUSTNESS": {
-    "description": "The name of a configuration value.",
-    "message": "Audio Robustness"
-  },
-  "DEMO_AUTO_CORRECT_DASH_DRIFT": {
-    "description": "The name of a configuration value.",
-    "message": "Auto-Correct [PROPER_NAME:DASH] Drift"
-  },
-  "DEMO_AUTO_LOW_LATENCY": {
-    "description": "The name of a configuration value.",
-    "message": "Auto Low Latency Streaming"
-  },
-  "DEMO_AUTO_SHOW_TEXT": {
-    "description": "The name of a configuration value.",
-    "message": "Auto-Show Text"
-  },
-  "DEMO_AUTO_SHOW_TEXT_NEVER": {
-    "description": "The name of a configuration value.",
-    "message": "Never"
-  },
-  "DEMO_AUTO_SHOW_TEXT_ALWAYS": {
-    "description": "The name of a configuration value.",
-    "message": "Always"
-  },
-  "DEMO_AUTO_SHOW_TEXT_IF_PREFERRED_TEXT_LANGUAGE": {
-    "description": "The name of a configuration value.",
-    "message": "If preferred text language"
-  },
-  "DEMO_AUTO_SHOW_TEXT_IF_SUBTITLES_MAY_BE_NEEDED": {
-    "description": "The name of a configuration value.",
-    "message": "If subtitles may be needed"
-  },
-  "DEMO_AVAILABILITY_WINDOW_OVERRIDE": {
-    "description": "The name of a configuration value.",
-    "message": "Availability Window Override"
-  },
-  "DEMO_AXINOM": {
-    "description": "Text that describes an asset that comes from the Axinom asset library.",
-    "message": "[PROPER_NAME:Axinom]"
-  },
-  "DEMO_AZURE_MEDIA_SERVICES": {
-    "description": "Text that describes an asset that comes from the Azure Media Services asset library.",
-    "message": "[PROPER_NAME:Azure Media Services]"
-  },
-  "DEMO_BACKOFF_FACTOR": {
-    "description": "The name of a configuration value.",
-    "message": "Backoff Factor"
-  },
-  "DEMO_BANDWIDTH_DOWNGRADE": {
-    "description": "The name of a configuration value.",
-    "message": "Bandwidth Downgrade Target"
-  },
-  "DEMO_BANDWIDTH_ESTIMATE": {
-    "description": "The name of a configuration value.",
-    "message": "Default Bandwidth Estimate"
-  },
-  "DEMO_BANDWIDTH_UPGRADE": {
-    "description": "The name of a configuration value.",
-    "message": "Bandwidth Upgrade Target"
-  },
-  "DEMO_BASE_DELAY": {
-    "description": "The name of a configuration value.",
-    "message": "Base Delay"
-  },
-  "DEMO_BITCODIN": {
-    "description": "Text that describes an asset that comes from the Bitcodin asset library.",
-    "message": "[PROPER_NAME:Bitcodin]"
-  },
-  "DEMO_BUFFERING_GOAL": {
-    "description": "The name of a configuration value.",
-    "message": "Buffering Goal"
-  },
-  "DEMO_BUFFER_BEHIND": {
-    "description": "The name of a configuration value.",
-    "message": "Buffer Behind"
-  },
-  "DEMO_CANCEL_BUTTON": {
-    "description": "A button to cancel the creation or editing of a custom asset.",
-    "message": "Cancel"
-  },
-  "DEMO_CAPTIONS": {
-    "description": "A tag that marks an asset as having closed captions.",
-    "message": "Captions"
-  },
-  "DEMO_CDN_HEADER": {
-    "description": "A header for a section of the footer, that contains links to various CDN (Content Delivery Network)-related things.",
-    "message": "[JARGON:CDN]"
-  },
-  "DEMO_CLEAR": {
-    "description": "Text that describes an asset that is not protected with any Digital Rights Management system.",
-    "message": "No [JARGON:DRM] protection"
-  },
-  "DEMO_CLEAR_KEY": {
-    "description": "Text that describes an asset that is protected with the Clear Key Digital Rights Management system.",
-    "message": "Clear Key [JARGON:DRM]"
-  },
-  "DEMO_CLOCK_SYNC_URI": {
-    "description": "The name of a configuration value.",
-    "message": "Clock Sync URI"
-  },
-  "DEMO_CLEAR_BUFFER_SWITCH": {
-    "description": "Clear video buffer on abr rendition switch.",
-    "message": "Clear buffer"
-  },
-  "DEMO_CMCD_SECTION_HEADER": {
-    "description": "The header for a section of configuration values.",
-    "message": "[JARGON:CMCD]"
-  },
-  "DEMO_COMPILED_DEBUG": {
-    "description": "A link in the footer, to the debug build of the demo.",
-    "message": "Compiled (Debug)"
-  },
-  "DEMO_COMPILED_RELEASE": {
-    "description": "A link in the footer, to the release build of the demo.",
-    "message": "Compiled (Release)"
-  },
-  "DEMO_CONNECTION_TIMEOUT": {
-    "description": "The name of a configuration value.",
-    "message": "Connection timeout"
-  },
-  "DEMO_CONFIG": {
-    "description": "A title on the configuration panel, labeling it as configuration.",
-    "message": "[PROPER_NAME:Shaka Player] Demo Config"
-  },
-  "DEMO_CONTAINER_SEARCH": {
-    "description": "A header on a search field that filters by container type.",
-    "message": "Container"
-  },
-  "DEMO_CONTAINERLESS": {
-    "description": "Text that describes an asset that has a stream with audio data not contained in a container.",
-    "message": "Containerless"
-  },
-  "DEMO_CONTENT_ID": {
-    "description": "The name of a configuration value.",
-    "message": "Content ID"
-  },
-  "DEMO_CUSTOM": {
-    "description": "Text that describes an asset that was defined by the user.",
-    "message": "Custom"
-  },
-  "DEMO_CUSTOM_CONTENT": {
-    "description": "A link in the header, that switches to a page configuration for custom content.",
-    "message": "CUSTOM CONTENT"
-  },
-  "DEMO_CUSTOM_INTRO_ONE": {
-    "description": "The first part of a message instructing users on how to add custom content.",
-    "message": "Try [PROPER_NAME:Shaka Player] with your own content!"
-  },
-  "DEMO_CUSTOM_INTRO_THREE": {
-    "description": "The third part of a message instructing users on how to add custom content.",
-    "message": "Custom assets will remain even after reloading the page."
-  },
-  "DEMO_CUSTOM_INTRO_TWO": {
-    "description": "The second part of a message instructing users on how to add custom content.",
-    "message": "Press the button below to add a custom asset."
-  },
-  "DEMO_CUSTOM_PLAYHEAD_TRACKER": {
-    "description": "The name of a configuration value.",
-    "message": "Custom playhead tracker"
-  },
-  "DEMO_DASH": {
-    "description": "Text that describes an asset that is packaged in a DASH manifest.",
-    "message": "[PROPER_NAME:DASH]"
-  },
-  "DEMO_DASH_IF": {
-    "description": "Text that describes an asset that comes from the Dash Industry Forum asset library.",
-    "message": "[PROPER_NAME:DASH-IF]"
-  },
-  "DEMO_DASH_SEQUENCE_MODE": {
-    "description": "The name of a configuration value.",
-    "message": "Enable DASH sequence mode"
-  },
-  "DEMO_DEFAULT_AUDIO_CODEC": {
-    "description": "The name of a configuration value.",
-    "message": "Default Audio Codec"
-  },
-  "DEMO_DEFAULT_PRESENTATION_DELAY": {
-    "description": "The name of a configuration value.",
-    "message": "Default Presentation Delay"
-  },
-  "DEMO_DEFAULT_VIDEO_CODEC": {
-    "description": "The name of a configuration value.",
-    "message": "Default Video Codec"
-  },
-  "DEMO_DELAY_LICENSE": {
-    "description": "The name of a configuration value.",
-    "message": "Delay License Request Until Played"
-  },
-  "DEMO_DELETE_CUSTOM": {
-    "description": "A button allowing users to delete a custom asset.",
-    "message": "Delete"
-  },
-  "DEMO_DELETE_CUSTOM_PROMPT": {
-    "description": "A prompt asking the user to confirm if they want to delete a custom asset.",
-    "message": "Delete this custom asset?"
-  },
-  "DEMO_DELETE_STORED_PROMPT": {
-    "description": "A prompt asking the user if they want to delete the offline copy of an asset.",
-    "message": "Delete the offline copy?"
-  },
-  "DEMO_DEMO_MODE_HEADER": {
-    "description": "A header for a section of the footer, that allows the user to switch between different modes.",
-    "message": "DEMO MODE"
-  },
-  "DEMO_DISABLE_AUDIO": {
-    "description": "The name of a configuration value.",
-    "message": "Disable Audio"
-  },
-  "DEMO_DISABLE_TEXT": {
-    "description": "The name of a configuration value.",
-    "message": "Disable Text"
-  },
-  "DEMO_DISABLE_THUMBNAILS": {
-    "description": "The name of a configuration value.",
-    "message": "Disable Thumbnails"
-  },
-  "DEMO_DISABLE_VIDEO": {
-    "description": "The name of a configuration value.",
-    "message": "Disable Video"
-  },
-  "DEMO_DISABLE_XLINK_PROCESSING": {
-    "description": "The name of a configuration value.",
-    "message": "Disable [JARGON:Xlink] processing"
-  },
-  "DEMO_DISPATCH_ALL_EMSG_BOXES": {
-    "description": "The name of a configuration value.",
-    "message": "Dispatch all [JARGON:emsg] boxes"
-  },
-  "DEMO_DOCUMENTATION": {
-    "description": "A link in the footer, to the Shaka Player documentation.",
-    "message": "Documentation"
-  },
-  "DEMO_DRM_RETRY_SECTION_HEADER": {
-    "description": "The header for a section of configuration values.",
-    "message": "[JARGON:DRM] Retry Parameters"
-  },
-  "DEMO_DRM_SEARCH": {
-    "description": "A header on a search field that filters by whether or not the asset is protected by a Digital Rights Management system.",
-    "message": "[JARGON:DRM]"
-  },
-  "DEMO_DRM_SECTION_HEADER": {
-    "description": "The header for a section of configuration values.",
-    "message": "[JARGON:DRM]"
-  },
-  "DEMO_DRM_SESSION_TYPE": {
-    "description": "The name of a configuration value.",
-    "message": "Session Type"
-  },
-  "DEMO_DRM_SYSTEM": {
-    "description": "The label on a field that allows users to provide a Digital Rights Management (DRM) system identifier for a custom asset.",
-    "message": "Custom [JARGON:DRM] System"
-  },
-  "DEMO_DRM_TAB": {
-    "description": "The header for a tab within the custom asset creation dialog.",
-    "message": "[JARGON:DRM]"
-  },
-  "DEMO_DURATION_BACKOFF": {
-    "description": "The name of a configuration value.",
-    "message": "Duration Backoff"
-  },
-  "DEMO_EDIT_CUSTOM": {
-    "description": "A button allowing users to edit a custom asset.",
-    "message": "Edit"
-  },
-  "DEMO_ENABLED": {
-    "description": "The name of a configuration value.",
-    "message": "Enabled"
-  },
-  "DEMO_ENABLE_AUDIO_GROUPS": {
-    "description": "The name of a configuration value.",
-    "message": "Enable Audio Groups"
-  },
-  "DEMO_EXTRA_SHAKA_PLAYER_CONFIG": {
-    "description": "A label for a form field where extra Shaka Player configuration can be set",
-    "message": "Extra [PROPER_NAME:Shaka Player] configuration ([JARGON:JSON])"
-  },
-  "DEMO_EXTRA_TAB": {
-    "description": "The header for a tab within the custom asset creation dialog.",
-    "message": "Extra Config"
-  },
-  "DEMO_FAIRPLAY": {
-    "description": "Text that describes an asset that is protected with the Fairplay Digital Rights Management system.",
-    "message": "[PROPER_NAME:Fairplay] [JARGON:DRM]"
-  },
-  "DEMO_FAST_HALF_LIFE": {
-    "description": "The name of a configuration value.",
-    "message": "Fast half life"
-  },
-  "DEMO_FORCE_HTTPS": {
-    "description": "The name of a configuration value.",
-    "message": "Force [JARGON:HTTPS]"
-  },
-  "DEMO_FORCE_TRANSMUX": {
-    "description": "The name of a configuration value.",
-    "message": "Force Transmux"
-  },
-  "DEMO_INSERT_FAKE_ENCRYPTION_IN_INIT": {
-    "description": "The name of a configuration value.",
-    "message": "Insert fake encryption in init segments when needed by the platform."
-  },
-  "DEMO_FRONT_INTRO_DISMISS": {
-    "description": "A button allowing users to dismiss the intro message.",
-    "message": "Dismiss"
-  },
-  "DEMO_FRONT_INTRO_ONE": {
-    "description": "The first part of a message introducing the demo to new users.",
-    "message": "This is a demo of Google's [PROPER_NAME:Shaka Player], a JavaScript library for adaptive video streaming."
-  },
-  "DEMO_FRONT_INTRO_TWO": {
-    "description": "The second part of a message introducing the demo to new users.",
-    "message": "Choose a video to playback; more assets are available via the \"all content\" tab."
-  },
-  "DEMO_FUZZ_FACTOR": {
-    "description": "The name of a configuration value.",
-    "message": "Fuzz Factor"
-  },
-  "DEMO_GAP_DETECTION_THRESHOLD": {
-    "description": "The name of a configuration value.",
-    "message": "Gap detection threshold"
-  },
-  "DEMO_GAP_JUMP_TIMER_TIME": {
-    "description": "The name of a configuration value.",
-    "message": "Gap jump timer time"
-  },
-  "DEMO_GPAC": {
-    "description": "Text that describes an asset that comes from the GPAC project asset library.",
-    "message": "[PROPER_NAME:GPAC]"
-  },
-  "DEMO_HEADERS_TAB": {
-    "description": "The header for a tab within the custom asset creation dialog.",
-    "message": "Headers"
-  },
-  "DEMO_HDR_LEVEL": {
-    "description": "The name of a configuration value.",
-    "message": "Preferred HDR Level"
-  },
-  "DEMO_HDR_LEVEL_AUTO": {
-    "description": "The name of a configuration value.",
-    "message": "Auto Detect"
-  },
-  "DEMO_HDR_LEVEL_HLG": {
-    "description": "The name of a configuration value.",
-    "message": "[PROPER_NAME:HLG]"
-  },
-  "DEMO_HDR_LEVEL_NONE": {
-    "description": "The name of a configuration value.",
-    "message": "No Preference"
-  },
-  "DEMO_HDR_LEVEL_PQ": {
-    "description": "The name of a configuration value.",
-    "message": "[PROPER_NAME:PQ]"
-  },
-  "DEMO_HDR_LEVEL_SDR": {
-    "description": "The name of a configuration value.",
-    "message": "[PROPER_NAME:SDR]"
-  },
-  "DEMO_HIGH_DEFINITION": {
-    "description": "Text that describes an asset that has a high definition video stream.",
-    "message": "High definition"
-  },
-  "DEMO_HIGH_DEFINITION_SEARCH": {
-    "description": "A tooltip for an optional search term.",
-    "message": "Filters for assets with at least one high-definition video stream."
-  },
-  "DEMO_HLS": {
-    "description": "Text that describes an asset that is packaged in an HLS manifest.",
-    "message": "[PROPER_NAME:HLS]"
-  },
-  "DEMO_HLS_SEQUENCE_MODE": {
-    "description": "The name of a configuration value.",
-    "message": "Enable HLS sequence mode"
-  },
-  "DEMO_HLS_TAB": {
-    "description": "The header for a tab within the custom asset creation dialog.",
-    "message": "[PROPER_NAME:HLS]"
-  },
-  "DEMO_HOME": {
-    "description": "A link in the header, that switches to a page configuration for viewing the curated set of front-page content.",
-    "message": "HOME"
-  },
-  "DEMO_ICON_URL": {
-    "description": "The label on a field that allows users to provide an icon for a custom asset.",
-    "message": "Icon URL"
-  },
-  "DEMO_IGNORE_DASH_DRM": {
-    "description": "The name of a configuration value.",
-    "message": "Ignore [PROPER_NAME:DASH] [JARGON:DRM] Info"
-  },
-  "DEMO_IGNORE_DASH_EMPTY_ADAPTATION_SET": {
-    "description": "The name of a configuration value.",
-    "message": "Ignore empty [PROPER_NAME:DASH] [JARGON:AdaptationSets]"
-  },
-  "DEMO_IGNORE_DASH_MAX_SEGMENT_DURATION": {
-    "description": "The name of a configuration value.",
-    "message": "Ignore [PROPER_NAME:DASH] [JARGON:maxSegmentDuration]"
-  },
-  "DEMO_IGNORE_DASH_SUGGESTED_PRESENTATION_DELAY": {
-    "description": "The name of a configuration value.",
-    "message": "Ignore [PROPER_NAME:DASH] [JARGON:suggestedPresentationDelay]"
-  },
-  "DEMO_IGNORE_DEVICE_PIXEL_RATIO": {
-    "description": "The name of a configuration value.",
-    "message": "Ignore device pixel ratio"
-  },
-  "DEMO_IGNORE_HLS_TEXT_FAILURES": {
-    "description": "The name of a configuration value.",
-    "message": "Ignore [PROPER_NAME:HLS] Text Stream Failures"
-  },
-  "DEMO_IGNORE_HLS_IMAGE_FAILURES": {
-    "description": "The name of a configuration value.",
-    "message": "Ignore [PROPER_NAME:HLS] Image Stream Failures"
-  },
-  "DEMO_IMA_ASSET_KEY": {
-    "description": "The label on a field that allows users to provide an asset key for a custom asset.",
-    "message": "Asset key (for LIVE DAI Content)"
-  },
-  "DEMO_IMA_CONTENT_SRC_ID": {
-    "description": "The label on a field that allows users to provide a content source id for a custom asset.",
-    "message": "Asset key (for VOD DAI Content)"
-  },
-  "DEMO_IMA_MANIFEST_TYPE": {
-    "description": "The label on a field that allows users to provide a manifest type for a custom asset.",
-    "message": "Manifest type (for DAI Content)"
-  },
-  "DEMO_IMA_VIDEO_ID": {
-    "description": "The label on a field that allows users to provide a video id for a custom asset.",
-    "message": "Video ID (for VOD DAI Content)"
-  },
-  "DEMO_IGNORE_MANIFEST_PROGRAM_DATE_TIME": {
-    "description": "The name of a configuration value.",
-    "message": "Ignore Program Date Time from manifest"
-  },
-  "DEMO_IGNORE_MANIFEST_TIMESTAMPS_IN_SEGMENTS_MODE": {
-    "description": "The name of a configuration value.",
-    "message": "Ignore Manifest Timestamps in Segments Mode"
-  },
-  "DEMO_IGNORE_MIN_BUFFER_TIME": {
-    "description": "The name of a configuration value.",
-    "message": "Ignore Min Buffer Time"
-  },
-  "DEMO_IGNORE_TEXT_FAILURES": {
-    "description": "The name of a configuration value.",
-    "message": "Ignore Text Stream Failures"
-  },
-  "DEMO_INACCURATE_MANIFEST_TOLERANCE": {
-    "message": "Inaccurate Manifest Tolerance",
-    "description": "The name of a configuration value."
-  },
-  "DEMO_INITIAL_SEGMENT_LIMIT": {
-    "description": "The name of a configuration value.",
-    "message": "Initial Segment Limit"
-  },
-  "DEMO_INVALID_JSON_CONFIG_ERROR": {
-    "description": "An error message for an invalid JSON configuration.",
-    "message": "Invalid JSON configuration"
-  },
-  "DEMO_IRT": {
-    "description": "Text that describes an asset that comes from the Institut f\u00fcr Rundfunktechnik asset library.",
-    "message": "[PROPER_NAME:IRT]"
-  },
-  "DEMO_JSDELIVR": {
-    "description": "A link in the footer, to Shaka Player in the jsDelivr CDN.",
-    "message": "[PROPER_NAME:jsDelivr]"
-  },
-  "DEMO_LANGUAGE_SECTION_HEADER": {
-    "description": "The header for a section of configuration values.",
-    "message": "Language"
-  },
-  "DEMO_LCEVC": {
-    "description": "Text that describes an asset that has LCEVC.",
-    "message": "[PROPER_NAME:LCEVC]"
-  },
-  "DEMO_LCEVC_DRAW_LOGO": {
-    "description": "LCEVC Watermark on the top left hand corner of the canvas.",
-    "message": "Draw [PROPER_NAME:LCEVC] Logo"
-  },
-  "DEMO_LCEVC_DYNAMIC_PERFORMANCE_SCALING": {
-    "description": "Dynamic Performance scaling for enabling/disabling LCEVC decoding based on decode performance.",
-    "message": "[PROPER_NAME:LCEVC] [JARGON:Dynamic Performance scaling]"
-  },
-  "DEMO_LCEVC_LOG_LEVEL": {
-    "description": "Log Level for LCEVC Lib (0-5)",
-    "message": "[PROPER_NAME:LCEVC] Log Level"
-  },
-  "DEMO_LCEVC_SECTION_HEADER": {
-    "description": "The header for a section of configuration values.",
-    "message": "[PROPER_NAME:MPEG-5 Part-2 LCEVC]"
-  },
-  "DEMO_LIBRARIES": {
-    "description": "A link in the footer, to Shaka Player in the Google Hosted Libraries CDN.",
-    "message": "[PROPER_NAME:Google Hosted Libraries]"
-  },
-  "DEMO_LICENSE": {
-    "description": "A link in the footer, to the Apache open-source license.",
-    "message": "[PROPER_NAME:Apache] License"
-  },
-  "DEMO_LICENSE_CERTIFICATE_URL": {
-    "description": "The label on a field that allows users to provide a license certificate for a custom asset.",
-    "message": "Custom License Certificate URL"
-  },
-  "DEMO_LICENSE_HEADER_NAME": {
-    "description": "A field for picking the name of the header to add.",
-    "message": "Header Name"
-  },
-  "DEMO_LICENSE_HEADER_TITLE": {
-    "description": "A header denoting a set of fields to add a license header.",
-    "message": "License Header"
-  },
-  "DEMO_LICENSE_HEADER_VALUE": {
-    "description": "A field for picking the value of the header to add.",
-    "message": "Header Value"
-  },
-  "DEMO_LICENSE_SERVER_URL": {
-    "description": "The label on a field that allows users to provide a license server for a custom asset.",
-    "message": "Custom License Server URL"
-  },
-  "DEMO_LIVE": {
-    "description": "Text that describes an asset that is being broadcast live.",
-    "message": "Live"
-  },
-  "DEMO_LIVE_SEARCH": {
-    "description": "A header on a search field that filters by whether the asset is live or not.",
-    "message": "Live"
-  },
-  "DEMO_LIVE_SEGMENTS_DELAY": {
-    "description": "The name of a configuration value.",
-    "message": "Live segments delay"
-  },
-  "DEMO_LIVE_SYNC": {
-    "description": "The name of a configuration value.",
-    "message": "Live sync"
-  },
-  "DEMO_LIVE_SYNC_MAX_LATENCY": {
-    "description": "The name of a configuration value.",
-    "message": "Max latency for live sync"
-  },
-  "DEMO_LIVE_SYNC_PLAYBACK_RATE": {
-    "description": "The name of a configuration value.",
-    "message": "Playback rate for live sync"
-  },
-  "DEMO_LOG_LEVEL": {
-    "description": "The name of a configuration value.",
-    "message": "Log Level"
-  },
-  "DEMO_LOG_LEVEL_DEBUG": {
-    "description": "The name of a log level, describing how detailed logging should be.",
-    "message": "Debug"
-  },
-  "DEMO_LOG_LEVEL_INFO": {
-    "description": "The name of a log level, describing how detailed logging should be.",
-    "message": "Info"
-  },
-  "DEMO_LOG_LEVEL_V": {
-    "description": "The name of a log level, describing how detailed logging should be.",
-    "message": "Verbose"
-  },
-  "DEMO_LOG_LEVEL_VV": {
-    "description": "The name of a log level, describing how detailed logging should be.",
-    "message": "Very Verbose"
-  },
-  "DEMO_LOG_LICENSE_EXCHANGE": {
-    "description": "The label on a field that allows users to select whether to log data about the license exchange",
-    "message": "Log license exchange data"
-  },
-  "DEMO_LOW_LATENCY": {
-    "description": "The name of a configuration value.",
-    "message": "Low Latency Streaming"
-  },
-  "DEMO_MAIN_TAB": {
-    "description": "The header for a tab within the custom asset creation dialog.",
-    "message": "Main"
-  },
-  "DEMO_MANIFEST_RETRY_SECTION_HEADER": {
-    "description": "The header for a section of configuration values.",
-    "message": "Manifest Retry Parameters"
-  },
-  "DEMO_MANIFEST_SEARCH": {
-    "description": "A header on a search field that filters by manifest type.",
-    "message": "Manifest"
-  },
-  "DEMO_MANIFEST_SECTION_HEADER": {
-    "description": "The header for a section of configuration values.",
-    "message": "Manifest"
-  },
-  "DEMO_MANIFEST_URL": {
-    "description": "The label on a field that allows users to provide a manifest URL for a custom asset.",
-    "message": "Manifest URL"
-  },
-  "DEMO_MANIFEST_URL_ERROR": {
-    "description": "An error that is displayed if the user does not provide a manifest URL for a custom asset or identification fields in the Google Ad Manager system.",
-    "message": "Must have a manifest URL, or IMA DAI id fields."
-  },
-  "DEMO_MAX_ATTEMPTS": {
-    "description": "The name of a configuration value.",
-    "message": "Max Attempts"
-  },
-  "DEMO_MAX_BANDWIDTH": {
-    "description": "The name of a configuration value.",
-    "message": "Max Bandwidth"
-  },
-  "DEMO_MAX_DISABLED_TIME": {
-    "description": "The maximum amount of seconds a variant can be disabled when an error is thrown.",
-    "message": "Max Variant Disabled Time"
-  },
-  "DEMO_MAX_FRAMERATE": {
-    "description": "The name of a configuration value.",
-    "message": "Max Framerate"
-  },
-  "DEMO_MAX_HEIGHT": {
-    "description": "The name of a configuration value.",
-    "message": "Max Height"
-  },
-  "DEMO_MAX_PIXELS": {
-    "description": "The name of a configuration value.",
-    "message": "Max Pixels"
-  },
-  "DEMO_MAX_WIDTH": {
-    "description": "The name of a configuration value.",
-    "message": "Max Width"
-  },
-  "DEMO_MEDIA_SOURCE_SECTION_HEADER": {
-    "description": "The header for a section of configuration values.",
-    "message": "Media source"
-  },
-  "DEMO_METACDN": {
-    "description": "Text that describes an asset that comes from the MetaCDN asset library.",
-    "message": "[PROPER_NAME:MetaCDN]"
-  },
-  "DEMO_MICROSOFT": {
-    "description": "Text that describes an asset that comes from the Microsoft.",
-    "message": "[PROPER_NAME:Microsoft]"
-  },
-  "DEMO_MIME_TYPE": {
-    "description": "The label on a field that allows users to provide a MIME type for a custom asset.",
-    "message": "MIME Type"
-  },
-  "DEMO_MIN_BANDWIDTH": {
-    "description": "The name of a configuration value.",
-    "message": "Min Bandwidth"
-  },
-  "DEMO_MIN_BYTES": {
-    "description": "The name of a configuration value.",
-    "message": "Min Bytes"
-  },
-  "DEMO_MIN_HDCP_VERSION": {
-    "description": "The name of a configuration value.",
-    "message": "Min HDCP version"
-  },
-  "DEMO_MIN_FRAMERATE": {
-    "description": "The name of a configuration value.",
-    "message": "Min Framerate"
-  },
-  "DEMO_MIN_HEIGHT": {
-    "description": "The name of a configuration value.",
-    "message": "Min Height"
-  },
-  "DEMO_MIN_PIXELS": {
-    "description": "The name of a configuration value.",
-    "message": "Min Pixels"
-  },
-  "DEMO_MIN_TOTAL_BYTES": {
-    "description": "The name of a configuration value.",
-    "message": "Min total Bytes"
-  },
-  "DEMO_MIN_WIDTH": {
-    "description": "The name of a configuration value.",
-    "message": "Min Width"
-  },
-  "DEMO_MP2TS": {
-    "description": "Text that describes an asset that uses the MPEG-2 TS container.",
-    "message": "[JARGON:MPEG-2 TS]"
-  },
-  "DEMO_MP4": {
-    "description": "Text that describes an asset that uses the MP4 container.",
-    "message": "[JARGON:MP4]"
-  },
-  "DEMO_MSS": {
-    "description": "Text that describes an asset that is packaged in an MSS manifest.",
-    "message": "[PROPER_NAME:MSS]"
-  },
-  "DEMO_MSS_SEQUENCE_MODE": {
-    "description": "The name of a configuration value.",
-    "message": "Enable MSS sequence mode"
-  },
-  "DEMO_MULTIPLE_LANGUAGES": {
-    "description": "A tag that marks an asset as having multiple languages.",
-    "message": "Multiple languages"
-  },
-  "DEMO_NAME": {
-    "description": "The label on a field that allows users to provide a name for a custom asset.",
-    "message": "Name"
-  },
-  "DEMO_NAME_ERROR": {
-    "description": "An error message that is displayed if the user presents an invalid name for a custom asset.",
-    "message": "Must be a unique name."
-  },
-  "DEMO_NETWORK_INFORMATION": {
-    "description": "The name of a configuration value.",
-    "message": "Use Network Information API."
-  },
-  "DEMO_NIMBLE_STREAMER": {
-    "description": "Text that describes an asset that comes from the Nimble Streamer asset library.",
-    "message": "[PROPER_NAME:Nimble Streamer]"
-  },
-  "DEMO_NPM": {
-    "description": "A link in the footer, to the Nexus Package Manager page for Shaka Player.",
-    "message": "Package on [PROPER_NAME:NPM]"
-  },
-  "DEMO_NUMBER_DECIMAL_WARNING": {
-    "description": "A warning on number inputs, telling the user what the expected input format is.",
-    "message": "Must be a positive number."
-  },
-  "DEMO_NUMBER_INTEGER_WARNING": {
-    "description": "A warning on number inputs, telling the user what the expected input format is.",
-    "message": "Must be a positive integer."
-  },
-  "DEMO_NUMBER_NONZERO_DECIMAL_WARNING": {
-    "description": "A warning on number inputs, telling the user what the expected input format is.",
-    "message": "Must be a positive, nonzero number."
-  },
-  "DEMO_NUMBER_NONZERO_INTEGER_WARNING": {
-    "description": "A warning on number inputs, telling the user what the expected input format is.",
-    "message": "Must be a positive, nonzero integer."
-  },
-  "DEMO_NUMBER_OF_PARALLEL_DOWNLOADS": {
-    "description": "The name of a configuration value.",
-    "message": "Number of parallel downloads."
-  },
-  "DEMO_OBSERVE_QUALITY_CHANGES": {
-    "description": "The name of a configuration value.",
-    "message": "Observe media quality changes"
-  },
-  "DEMO_OFFLINE": {
-    "description": "A tag that marks an asset as being possible to download.",
-    "message": "Downloadable"
-  },
-  "DEMO_OFFLINE_SEARCH": {
-    "description": "A tooltip for an optional search term.",
-    "message": "Filters for assets that can be stored offline."
-  },
-  "DEMO_OFFLINE_SECTION_HEADER": {
-    "description": "The header for a section of configuration values.",
-    "message": "Offline"
-  },
-  "DEMO_FAILURE_MISC": {
-    "description": "An error displayed if Shaka Player fails to load for a miscellaneous reason.",
-    "message": "Shaka Player failed to load! If you are using an ad blocker, try switching to compiled mode at the bottom of the page."
-  },
-  "DEMO_FAILURE_NO_BROWSER_SUPPORT": {
-    "description": "An error displayed if Shaka Player is unable to load due to lack of browser support.",
-    "message": "Your browser is not supported!"
-  },
-  "DEMO_HLS_FULL_MIME_TYPE": {
-    "description": "The label on a field that allows users to provide a full mime type for a custom asset.",
-    "message": "Full Mime Type for Playing Media Playlists Directly"
-  },
-  "DEMO_PARSE_INBAND_PSSH_ENABLED": {
-    "description": "The name of a configuration value.",
-    "message": "Parse inband 'pssh' from media segments"
-  },
-  "DEMO_PLAY": {
-    "description": "A button to play the attached asset.",
-    "message": "Play"
-  },
-  "DEMO_PLAYREADY": {
-    "description": "Text that describes an asset that is protected with the Playready Digital Rights Management system.",
-    "message": "[PROPER_NAME:PlayReady] [JARGON:DRM]"
-  },
-  "DEMO_PREFER_FORCED_SUBS": {
-    "description": "The name of a configuration value.",
-    "message": "Prefer Forced Subs"
-  },
-  "DEMO_PREFER_NATIVE_HLS": {
-    "description": "The name of a configuration value.",
-    "message": "Prefer native HLS playback when available"
-  },
-  "DEMO_PROJECT_LINKS_HEADER": {
-    "description": "A header for a section of the footer, that contains links to various project-related things.",
-    "message": "PROJECT LINKS"
-  },
-  "DEMO_PROMPT_NO": {
-    "description": "A button to say 'no' to a question (for example, DEMO_DELETE_CUSTOM_PROMPT).",
-    "message": "No"
-  },
-  "DEMO_PROMPT_YES": {
-    "description": "A button to say 'yes' to a question (for example, DEMO_DELETE_CUSTOM_PROMPT).",
-    "message": "Yes"
-  },
-  "DEMO_REBUFFERING_GOAL": {
-    "description": "The name of a configuration value.",
-    "message": "Rebuffering Goal"
-  },
-  "DEMO_REPORT_BUG": {
-    "description": "A link in the header, that files a bug report.",
-    "message": "REPORT BUG"
-  },
-  "DEMO_RESTRICT_TO_ELEMENT_SIZE": {
-    "description": "The name of a configuration value.",
-    "message": "Restrict to element size"
-  },
-  "DEMO_RESTRICT_TO_SCREEN_SIZE": {
-    "description": "The name of a configuration value.",
-    "message": "Restrict to screen size"
-  },
-  "DEMO_RESTRICTIONS_SECTION_HEADER": {
-    "description": "The header for a section of configuration values.",
-    "message": "Restrictions"
-  },
-  "DEMO_SAFE_MARGIN_SWITCH": {
-    "description": "Safe margin on abr switch rendition",
-    "message": "safe margin"
-  },
-  "DEMO_SAFE_SEEK_OFFSET": {
-    "description": "The name of a configuration value.",
-    "message": "Safe Seek Offset"
-  },
-  "DEMO_SAFE_SKIP_DISTANCE": {
-    "description": "The name of a configuration value.",
-    "message": "Safe Skip Distance"
-  },
-  "DEMO_SAVE_BUTTON": {
-    "description": "A button to save a custom asset.",
-    "message": "Save"
-  },
-  "DEMO_SEGMENT_RELATIVE_VTT_TIMING": {
-    "description": "The name of a configuration value.",
-    "message": "Enable segment-relative VTT Timing"
-  },
-  "DEMO_SESSION_ID": {
-    "description": "The name of a configuration value.",
-    "message": "Session ID"
-  },
-  "DEMO_SHAKA": {
-    "description": "Text that describes an asset that comes from the Shaka Player asset library.",
-    "message": "[PROPER_NAME:Shaka]"
-  },
-  "DEMO_SLOW_HALF_LIFE": {
-    "description": "The name of a configuration value.",
-    "message": "Slow half life"
-  },
-  "DEMO_SHAKA_CONTROLS": {
-    "description": "The name of a configuration value.",
-    "message": "[PROPER_NAME:Shaka] Controls"
-  },
-  "DEMO_SOURCE": {
-    "description": "A link in the footer, to the Shaka Player source on GitHub.",
-    "message": "Source on [PROPER_NAME:GitHub]"
-  },
-  "DEMO_SOURCE_BUFFER_EXTRA_FEATURES": {
-    "description": "The name of a configuration value.",
-    "message": "Source buffer extra features"
-  },
-  "DEMO_SOURCE_SEARCH": {
-    "description": "A header on a search field that filters by the source of the asset.",
-    "message": "Source"
-  },
-  "DEMO_STALL_DETECTOR_ENABLED": {
-    "description": "The name of a configuration value.",
-    "message": "Stall Detector Enabled"
-  },
-  "DEMO_STALL_THRESHOLD": {
-    "description": "The name of a configuration value.",
-    "message": "Stall Threshold"
-  },
-  "DEMO_STALL_TIMEOUT": {
-    "description": "The name of a configuration value.",
-    "message": "Stall timeout"
-  },
-  "DEMO_START_AT_SEGMENT_BOUNDARY": {
-    "description": "The name of a configuration value.",
-    "message": "Start At Segment Boundary"
-  },
-  "DEMO_STORED": {
-    "description": "A tag that marks an asset as being downloaded by the user.",
-    "message": "Downloaded"
-  },
-  "DEMO_STORED_SEARCH": {
-    "description": "A tooltip for an optional search term.",
-    "message": "Filters for assets that have been stored offline."
-  },
-  "DEMO_STREAMING_RETRY_SECTION_HEADER": {
-    "description": "The header for a section of configuration values.",
-    "message": "Streaming Retry Parameters"
-  },
-  "DEMO_STREAMING_SECTION_HEADER": {
-    "description": "The header for a section of configuration values.",
-    "message": "Streaming"
-  },
-  "DEMO_SUBTITLES": {
-    "description": "A tag that marks an asset as having subtitles.",
-    "message": "Subtitles"
-  },
-  "DEMO_SUBTITLES_SEARCH": {
-    "description": "A tooltip for an optional search term.",
-    "message": "Filters for assets with caption tracks, or embedded captions."
-  },
-  "DEMO_SUPPORT": {
-    "description": "A link in the footer, to a browser support test.",
-    "message": "Browser Support Test"
-  },
-  "DEMO_SURROUND": {
-    "description": "Text that describes an asset that has an a surround sound audio stream.",
-    "message": "Surround sound"
-  },
-  "DEMO_SURROUND_SEARCH": {
-    "description": "A tooltip for an optional search term.",
-    "message": "Filters for assets with at least one surround sound audio track."
-  },
-  "DEMO_SWITCH_INTERVAL": {
-    "description": "The name of a configuration value.",
-    "message": "Switch Interval"
-  },
-  "DEMO_TEXT_LANGUAGE": {
-    "description": "The name of a configuration value.",
-    "message": "Preferred Text Language"
-  },
-  "DEMO_TEXT_ROLE": {
-    "description": "The name of a configuration value.",
-    "message": "Preferred Text Role"
-  },
-  "DEMO_THUMBNAILS": {
-    "description": "Text that describes an asset that has a thumbnail stream.",
-    "message": "Thumbnails"
-  },
-  "DEMO_TIMEOUT": {
-    "description": "The name of a configuration value.",
-    "message": "Timeout Factor"
-  },
-  "DEMO_TRICK_MODE": {
-    "description": "A tag that marks an asset as having a trick mode track, which allows a VCR-like effect when fast forwarding or rewinding.",
-    "message": "Special [JARGON:trick mode] track"
-  },
-  "DEMO_TRICK_MODE_SEARCH": {
-    "description": "A tooltip for an optional search term.",
-    "message": "Filters for assets that have special video tracks to be used in [JARGON:trick mode] playback (aka fast-forward)."
-  },
-  "DEMO_TRICK_PLAY_CONTROLS": {
-    "description": "The name of a configuration value.",
-    "message": "Enabled [JARGON:Trick Play] Controls"
-  },
-  "DEMO_TRICK_PLAY_CONTROLS_WARNING": {
-    "description": "A tooltip that warns the user that a certain combination of config values cannot be picked.",
-    "message": "[JARGON:Trick Play] controls require the Shaka UI."
-  },
-  "DEMO_UI_LOCALE": {
-    "description": "The name of a configuration value.",
-    "message": "Preferred UI Locale"
-  },
-  "DEMO_ULTRA_HIGH_DEFINITION": {
-    "description": "Text that describes an asset that has an ultra-high definition video stream.",
-    "message": "Ultra-high definition"
-  },
-  "DEMO_UNCOMPILED": {
-    "description": "A link in the footer, to the uncompiled build of the demo.",
-    "message": "Uncompiled"
-  },
-  "DEMO_UNIFIED_STREAMING": {
-    "description": "Text that describes an asset that comes from the Unified Streaming asset library.",
-    "message": "[PROPER_NAME:Unified Streaming]"
-  },
-  "DEMO_UNSUPPORTED": {
-    "description": "A label that marks an asset as being unavailable, for some reason.",
-    "message": "Not Available"
-  },
-  "DEMO_UNSUPPORTED_DISABLED": {
-    "description": "An error message that shows why an asset cannot be stored offline: the asset cannot be played on the browser, at all.",
-    "message": "This asset is disabled."
-  },
-  "DEMO_UNSUPPORTED_NO_DASH_SUPPORT": {
-    "description": "An error message that shows why an asset cannot be stored or played.",
-    "message": "Your browser does not support [PROPER_NAME:MPEG-DASH] manifests."
-  },
-  "DEMO_UNSUPPORTED_NO_DOWNLOAD": {
-    "description": "An error message that shows why an asset cannot be stored offline: the asset cannot be downloaded.",
-    "message": "This asset cannot be downloaded."
-  },
-  "DEMO_UNSUPPORTED_NO_FORMAT_SUPPORT": {
-    "description": "An error message that shows why an asset cannot be stored or played.",
-    "message": "Your browser does not support the required video format."
-  },
-  "DEMO_UNSUPPORTED_NO_HLS_SUPPORT": {
-    "description": "An error message that shows why an asset cannot be stored or played.",
-    "message": "Your browser does not support [PROPER_NAME:HLS] manifests."
-  },
-  "DEMO_UNSUPPORTED_NO_KEY_SUPPORT": {
-    "description": "An error message that shows why an asset cannot be stored or played.",
-    "message": "Your browser does not support the required key systems."
-  },
-  "DEMO_UNSUPPORTED_NO_LICENSE_SUPPORT": {
-    "description": "An error message that shows why an asset cannot be stored offline: the browser cannot store protected content offline.",
-    "message": "Your browser does not support offline licenses for the required key systems."
-  },
-  "DEMO_UNSUPPORTED_NO_MSS_SUPPORT": {
-    "description": "An error message that shows why an asset cannot be stored or played.",
-    "message": "Your browser does not support [PROPER_NAME:MSS] manifests."
-  },
-  "DEMO_UNSUPPORTED_NO_OFFLINE": {
-    "description": "An error message that shows why an asset cannot be stored offline: the browser does not support storing things offline, in general.",
-    "message": "Your browser does not support offline storage."
-  },
-  "DEMO_UPDATE_EXPIRATION_TIME": {
-    "description": "The name of a configuration value.",
-    "message": "Update expiration time"
-  },
-  "DEMO_UPDATE_INTERVAL_SECONDS": {
-    "description": "The name of a configuration value.",
-    "message": "Update interval seconds"
-  },
-  "DEMO_UPLYNK": {
-    "description": "Text that describes an asset that comes from the Verizon Digital Media Services asset library.",
-    "message": "[PROPER_NAME:Verizon Digital Media Services]"
-  },
-  "DEMO_USE_HEADERS": {
-    "description": "The name of a configuration value.",
-    "message": "Use Headers"
-  },
-  "DEMO_USE_NATIVE_HLS_SAFARI": {
-    "description": "The name of a configuration value.",
-    "message": "Use native [PROPER_NAME:HLS] on Safari"
-  },
-  "DEMO_USE_PERSISTENT_LICENSES": {
-    "description": "The name of a configuration value.",
-    "message": "Use Persistent Licenses"
-  },
-  "DEMO_USE_SAFARI_BEHAVIOR_FOR_LIVE": {
-    "description": "The name of a configuration value.",
-    "message": "Use Safari behavior for live"
-  },
-  "DEMO_VIDEO_ROBUSTNESS": {
-    "description": "The name of a configuration value.",
-    "message": "Video Robustness"
-  },
-  "DEMO_VISUALIZER_AUTO_SCREENSHOT_TOGGLE": {
-    "description": "A configuration toggle that makes the visualizer take a screenshot when the presentation stalls.",
-    "message": "Take Screenshot On Stall"
-  },
-  "DEMO_VISUALIZER_BUTTON": {
-    "description": "A button on the video that opens or hides the visualizer.",
-    "message": "Buffer Visualizer"
-  },
-  "DEMO_VISUALIZER_SCREENSHOT_BUTTON": {
-    "description": "A button that takes a screenshot of the current visualizer state.",
-    "message": "Take Screenshot"
-  },
-  "DEMO_VNOVA": {
-    "description": "Text that describes an asset that comes from V-Nova.",
-    "message": "[PROPER_NAME:V-Nova]"
-  },
-  "DEMO_VOD": {
-    "description": "Text that describes an asset that is a VOD (Video On Delivery).",
-    "message": "[JARGON:VOD]"
-  },
-  "DEMO_WEBM": {
-    "description": "Text that describes an asset that uses the WebM container.",
-    "message": "[JARGON:WebM]"
-  },
-  "DEMO_WIDEVINE": {
-    "description": "Text that describes an asset that is protected with the Widevine Digital Rights Management system.",
-    "message": "[PROPER_NAME:Widevine] [JARGON:DRM]"
-  },
-  "DEMO_XLINK": {
-    "description": "A tag that marks an asset as containing one or more XLink.",
-    "message": "[JARGON:XLink]"
-  },
-  "DEMO_XLINK_FAIL_GRACEFULLY": {
-    "description": "The name of a configuration value.",
-    "message": "[JARGON:Xlink] Should Fail Gracefully"
-  },
-  "DEMO_XLINK_SEARCH": {
-    "description": "A tooltip for an optional search term.",
-    "message": "Filters for assets that have [JARGON:XLINK] tags in their manifests, so that they can be broken into multiple files."
-  },
-  "DEMO_SEGMENT_PREFETCH_LIMIT": {
-    "description": "Max number of segments to be prefetched ahead of current time position.",
-    "message": "Segment Prefetch Limit."
-  },
-  "DEMO_LOW_LATENCY_STREAM": {
-    "description": "A tag that marks an asset as low latency.",
-    "message": "Low Latency stream"
-  }
-}
diff --git a/demo/main.js b/demo/main.js
index b92a45adf..d19794af5 100644
--- a/demo/main.js
+++ b/demo/main.js
@@ -10,7 +10,6 @@ goog.provide('shakaDemo.Main');
 goog.require('ShakaDemoAssetInfo');
 goog.require('goog.asserts');
 goog.require('shakaDemo.CloseButton');
-goog.require('shakaDemo.MessageIds');
 goog.require('shakaDemo.Utils');
 goog.require('shakaDemo.Visualizer');
 goog.require('shakaDemo.VisualizerButton');
@@ -122,9 +121,8 @@ shakaDemo.Main = class {
    * This does not dispatch the shaka-main-loaded event, so it will not cause
    * the nav bar buttons to be set up.
    * @param {!shaka.ui.Overlay.FailReasonCode} reasonCode
-   * @return {!Promise}
    */
-  async initFailed(reasonCode) {
+  initFailed(reasonCode) {
     this.initCommon_();
 
     // Set up version links, so the user can switch to compiled mode if
@@ -155,25 +153,19 @@ shakaDemo.Main = class {
       element.classList.add('disabled-by-fail');
     }
 
-    // Because the UI did not load, this will need to set up a localization
-    // object manually.
-    this.localization_ = new shaka.ui.Localization(/* fallbackLocale= */ 'en');
-    this.localization_.changeLocale(navigator.languages || []);
-    await this.setupLocalization_();
-
     // Process a synthetic error about lack of browser support.
     const severity = shaka.util.Error.Severity.CRITICAL;
     let href = '';
     let message = '';
     switch (reasonCode) {
       case shaka.ui.Overlay.FailReasonCode.NO_BROWSER_SUPPORT:
-        message = this.getLocalizedString(
-            shakaDemo.MessageIds.FAILURE_NO_BROWSER_SUPPORT);
+        message = 'Your browser is not supported!';
         href = 'https://github.com/shaka-project/shaka-player#' +
                 'platform-and-browser-support-matrix';
         break;
       case shaka.ui.Overlay.FailReasonCode.PLAYER_FAILED_TO_LOAD:
-        message = this.getLocalizedString(shakaDemo.MessageIds.FAILURE_MISC);
+        message = 'Shaka Player failed to load! If you are using an adblocker' +
+            ', try switching to compiled mode at the bottom of the page.';
         break;
     }
     this.handleError_(severity, message, href);
@@ -205,7 +197,7 @@ shakaDemo.Main = class {
     // Optionally enter noinput mode. This has to happen before setting up the
     // player.
     this.noInput_ = 'noinput' in this.getParams_();
-    await this.setupPlayer_();
+    this.setupPlayer_();
     this.readHash_();
     window.addEventListener('hashchange', () => this.hashChanged_());
 
@@ -392,11 +384,8 @@ shakaDemo.Main = class {
     ui.configure(uiConfig);
   }
 
-  /**
-   * @return {!Promise}
-   * @private
-   */
-  async setupPlayer_() {
+  /** @private */
+  setupPlayer_() {
     const video = /** @type {!HTMLVideoElement} */ (this.video_);
     const ui = video['ui'];
     this.player_ = ui.getControls().getPlayer();
@@ -443,7 +432,6 @@ shakaDemo.Main = class {
     });
 
     this.localization_ = this.controls_.getLocalization();
-    await this.setupLocalization_();
 
     const drawerCloseButton = document.getElementById('drawer-close-button');
     drawerCloseButton.addEventListener('click', () => {
@@ -481,50 +469,6 @@ shakaDemo.Main = class {
     this.hideElement_(drawerCloseButton);
   }
 
-  /**
-   * @return {!Promise}
-   * @private
-   */
-  async setupLocalization_() {
-    // Set up localization lazy-loading.
-    const applyNewLocaleIfPossible = () => {
-      this.localizeHTMLElements_();
-      this.dispatchEventWithName_('shaka-main-locale-changed');
-    };
-    const UNKNOWN_LOCALES = shaka.ui.Localization.UNKNOWN_LOCALES;
-    this.localization_.addEventListener(UNKNOWN_LOCALES, (event) => {
-      for (const locale of event['locales']) {
-        // This will leave promise rejections uncaught; this is acceptable, as
-        // this function is actually expected to fail fairly often, and has
-        // built-in fallback behavior (from localization events) without needing
-        // to catch the promise rejection.
-        this.loadUILocale_(locale).then(() => {
-          if (locale == this.uiLocale_) {
-            applyNewLocaleIfPossible();
-          }
-        });
-      }
-    });
-    const LOCALE_CHANGED = shaka.ui.Localization.LOCALE_CHANGED;
-    this.localization_.addEventListener(LOCALE_CHANGED, (event) => {
-      applyNewLocaleIfPossible();
-    });
-    const initialLocaleLoads = [];
-    initialLocaleLoads.push(this.loadUILocale_(this.uiLocale_));
-    if (this.uiLocale_.includes('-')) {
-      // Also try to load the 'base' localization.
-      // This is so that, for example, the uiLocale_ is set to 'en-US', it will
-      // try to load 'en'.
-      initialLocaleLoads.push(this.loadUILocale_(this.uiLocale_.split('-')[0]));
-    }
-    if (!this.uiLocale_.startsWith('en')) {
-      // Load 'en' as a fallback option, if not already loaded.
-      initialLocaleLoads.push(this.loadUILocale_('en'));
-    }
-    await Promise.all(initialLocaleLoads);
-    this.localizeHTMLElements_();
-  }
-
   /** @return {boolean} */
   getIsDrawerOpen() {
     const drawer = document.querySelector('.mdl-layout__drawer');
@@ -719,13 +663,13 @@ shakaDemo.Main = class {
    *
    * @param {!ShakaDemoAssetInfo} asset
    * @param {boolean} needOffline True if offline support is required.
-   * @return {?shakaDemo.MessageIds} unsupportedReason
+   * @return {?string} unsupportedReason
    *   Null if asset is supported.
    */
   getAssetUnsupportedReason(asset, needOffline) {
     if (needOffline &&
         (!shaka.offline.Storage.support() || !this.initialStoredList_)) {
-      return shakaDemo.MessageIds.UNSUPPORTED_NO_OFFLINE;
+      return 'Your browser does not support offline storage.';
     }
 
     if (asset.source == shakaAssets.Source.CUSTOM) {
@@ -736,11 +680,11 @@ shakaDemo.Main = class {
 
     // Is the asset disabled?
     if (asset.disabled) {
-      return shakaDemo.MessageIds.UNSUPPORTED_DISABLED;
+      return 'This asset is disabled.';
     }
 
     if (needOffline && !asset.features.includes(shakaAssets.Feature.OFFLINE)) {
-      return shakaDemo.MessageIds.UNSUPPORTED_NO_DOWNLOAD;
+      return 'This asset cannot be downloaded.';
     }
 
     if (!asset.isClear() && !asset.isAes128()) {
@@ -748,7 +692,7 @@ shakaDemo.Main = class {
         return this.support_.drm[shakaAssets.identifierForKeySystem(drm)];
       });
       if (!hasSupportedDRM) {
-        return shakaDemo.MessageIds.UNSUPPORTED_NO_KEY_SUPPORT;
+        return 'Your browser does not support the required key systems.';
       }
       if (needOffline) {
         const hasSupportedOfflineDRM = asset.drm.some((drm) => {
@@ -757,7 +701,8 @@ shakaDemo.Main = class {
                  this.support_.drm[identifier].persistentState;
         });
         if (!hasSupportedOfflineDRM) {
-          return shakaDemo.MessageIds.UNSUPPORTED_NO_LICENSE_SUPPORT;
+          return 'Your browser does not support offline licenses for the ' +
+              'required key systems.';
         }
       }
     }
@@ -765,15 +710,15 @@ shakaDemo.Main = class {
     // Does the browser support the asset's manifest type?
     if (asset.features.includes(shakaAssets.Feature.DASH) &&
         !this.support_.manifest['mpd']) {
-      return shakaDemo.MessageIds.UNSUPPORTED_NO_DASH_SUPPORT;
+      return 'Your browser does not support MPEG-DASH manifests.';
     }
     if (asset.features.includes(shakaAssets.Feature.HLS) &&
         !this.support_.manifest['m3u8']) {
-      return shakaDemo.MessageIds.UNSUPPORTED_NO_HLS_SUPPORT;
+      return 'Your browser does not support HLS manifests.';
     }
     if (asset.features.includes(shakaAssets.Feature.MSS) &&
         !this.support_.manifest['ism']) {
-      return shakaDemo.MessageIds.UNSUPPORTED_NO_MSS_SUPPORT;
+      return 'Your browser does not support MSS manifests.';
     }
 
     // Does the asset contain a playable mime type?
@@ -794,7 +739,7 @@ shakaDemo.Main = class {
       return this.support_.media[type];
     });
     if (!hasSupportedMimeType) {
-      return shakaDemo.MessageIds.UNSUPPORTED_NO_FORMAT_SUPPORT;
+      return 'Your browser does not support the required video format.';
     }
 
     return null;
@@ -841,55 +786,6 @@ shakaDemo.Main = class {
     return this.nativeControlsEnabled_;
   }
 
-  /**
-   * Look through all elements in the DOM, and look for things tagged as having
-   * a localized string. Then, localize them.
-   *
-   * @private
-   */
-  localizeHTMLElements_() {
-    for (const element of document.querySelectorAll('[localized-string]')) {
-      const key = element.getAttribute('localized-string');
-      const value = shakaDemo.MessageIds[key];
-      if (value) {
-        element.textContent = this.getLocalizedString(value);
-      }
-    }
-  }
-
-  /**
-   * @param {!shakaDemo.MessageIds} string
-   * @return {string}
-   */
-  getLocalizedString(string) {
-    return this.localization_.resolve(string);
-  }
-
-  /**
-   * @param {string} locale
-   * @return {!Promise}
-   * @private
-   */
-  async loadUILocale_(locale) {
-    if (!locale) {
-      return;
-    }
-
-    const load = async (urlBase) => {
-      const url = urlBase + '/locales/' + locale + '.json';
-
-      try {
-        const text = await this.loadText_(url);
-        const obj = /** @type {!Object.<string, string>} */(JSON.parse(text));
-        const map = new Map(Object.entries(obj));
-        this.localization_.insert(locale, map);
-      } catch (error) {
-        console.warn('Unable to load locale', locale, 'for url', url);
-      }
-    };
-    await Promise.all([load('../ui'), load('../demo')]);
-  }
-
   /** @param {string} locale */
   setUILocale(locale) {
     this.uiLocale_ = locale;
@@ -1810,7 +1706,6 @@ shakaDemo.Main = class {
     // Always show the new error if:
     //   1. there is no error showing currently
     //   2. the new error is more severe than the old one
-    // Sadly, we do not (yet?) have localizations for error messages.
     if (this.currentErrorSeverity_ == null ||
         severity > this.currentErrorSeverity_) {
       this.errorDisplayLink_.href = href;
diff --git a/demo/search.js b/demo/search.js
index 5948b8bb0..7416c4256 100644
--- a/demo/search.js
+++ b/demo/search.js
@@ -11,7 +11,6 @@ goog.provide('shakaDemo.Search');
 goog.require('shakaDemo.AssetCard');
 goog.require('shakaDemo.BoolInput');
 goog.require('shakaDemo.InputContainer');
-goog.require('shakaDemo.MessageIds');
 goog.require('shakaDemo.SelectInput');
 goog.requireType('ShakaDemoAssetInfo');
 
@@ -60,12 +59,6 @@ shakaDemo.Search = class {
     document.addEventListener('shaka-main-offline-progress', () => {
       this.updateOfflineProgress_();
     });
-    document.addEventListener('shaka-main-locale-changed', () => {
-      this.remakeSearchDiv_(container);
-      this.remakeResultsDiv_();
-      // Update the componentHandler, to account for any new MDL elements added.
-      componentHandler.upgradeDom();
-    });
     document.addEventListener('shaka-main-page-changed', () => {
       if (!this.resultsDiv_.childNodes.length &&
           !container.classList.contains('hidden')) {
@@ -153,7 +146,7 @@ shakaDemo.Search = class {
       if (unsupportedReason) {
         c.markAsUnsupported(unsupportedReason);
       } else {
-        c.addButton(shakaDemo.MessageIds.PLAY, () => {
+        c.addButton('Play', () => {
           shakaDemoMain.loadAsset(asset);
           this.updateSelected_();
         });
@@ -270,7 +263,7 @@ shakaDemo.Search = class {
    * The term this represents.
    * @param {shakaDemo.Search.TermType} type
    * The type of term that this term is.
-   * @param {?shakaDemo.MessageIds} tooltip
+   * @param {?string} tooltip
    * @private
    */
   makeBooleanInput_(searchContainer, choice, type, tooltip) {
@@ -298,7 +291,7 @@ shakaDemo.Search = class {
    * Creates an input for a group of related but mutually-exclusive search
    * terms.
    * @param {!shakaDemo.InputContainer} searchContainer
-   * @param {!shakaDemo.MessageIds} name
+   * @param {string} name
    * @param {!Array.<!shakaDemo.Search.SearchTerm>} choices
    * An array of the terms in this term group.
    * @param {shakaDemo.Search.TermType} type
@@ -311,7 +304,7 @@ shakaDemo.Search = class {
     const nullOption = '---';
     const valuesObject = {};
     for (const term of choices) {
-      valuesObject[term] = shakaDemoMain.getLocalizedString(term);
+      valuesObject[term] = term;
     }
     valuesObject[nullOption] = nullOption;
     let lastValue = nullOption;
@@ -357,23 +350,18 @@ shakaDemo.Search = class {
     const coreContainer = new shakaDemo.InputContainer(
         container, /* headerText= */ null, shakaDemo.InputContainer.Style.FLEX,
         /* docLink= */ null);
-    this.makeSelectInput_(coreContainer,
-        shakaDemo.MessageIds.MANIFEST_SEARCH,
+    this.makeSelectInput_(coreContainer, 'Manifest',
         [Feature.DASH, Feature.HLS, Feature.MSS], FEATURE);
-    this.makeSelectInput_(coreContainer,
-        shakaDemo.MessageIds.CONTAINER_SEARCH,
+    this.makeSelectInput_(coreContainer, 'Container',
         [Feature.MP4, Feature.MP2TS, Feature.WEBM, Feature.CONTAINERLESS],
         FEATURE);
-    this.makeSelectInput_(coreContainer,
-        shakaDemo.MessageIds.DRM_SEARCH,
+    this.makeSelectInput_(coreContainer, 'DRM',
         Object.values(shakaAssets.KeySystem), DRM);
-    this.makeSelectInput_(coreContainer,
-        shakaDemo.MessageIds.SOURCE_SEARCH,
+    this.makeSelectInput_(coreContainer, 'Source',
         Object.values(shakaAssets.Source).filter((term) => {
           return term != shakaAssets.Source.CUSTOM;
         }), SOURCE);
-    this.makeSelectInput_(coreContainer,
-        shakaDemo.MessageIds.LIVE_SEARCH,
+    this.makeSelectInput_(coreContainer, 'Live',
         [Feature.LIVE, Feature.VOD], FEATURE);
 
     // Special terms.
@@ -382,29 +370,31 @@ shakaDemo.Search = class {
         container, /* headerText= */ null, containerStyle,
         /* docLink= */ null);
     this.makeBooleanInput_(specialContainer, Feature.HIGH_DEFINITION, FEATURE,
-        shakaDemo.MessageIds.HIGH_DEFINITION_SEARCH);
+        'Filters for assets with at least one high-definition video stream.');
     this.makeBooleanInput_(specialContainer, Feature.XLINK, FEATURE,
-        shakaDemo.MessageIds.XLINK_SEARCH);
+        'Filters for assets that have XLINK tags in their manifests, so that ' +
+        'they can be broken into multiple files.');
     this.makeBooleanInput_(specialContainer, Feature.SUBTITLES, FEATURE,
-        shakaDemo.MessageIds.SUBTITLES_SEARCH);
+        'Filters for assets with caption tracks, or embedded captions.');
     this.makeBooleanInput_(specialContainer, Feature.TRICK_MODE, FEATURE,
-        shakaDemo.MessageIds.TRICK_MODE_SEARCH);
+        'Filters for assets that have special video tracks to be used in ' +
+        'trick mode playback (aka fast-forward).');
     this.makeBooleanInput_(specialContainer, Feature.SURROUND, FEATURE,
-        shakaDemo.MessageIds.SURROUND_SEARCH);
+        'Filters for assets with at least one surround sound audio track.');
     this.makeBooleanInput_(specialContainer, Feature.OFFLINE, FEATURE,
-        shakaDemo.MessageIds.OFFLINE_SEARCH);
+        'Filters for assets that can be stored offline.');
     this.makeBooleanInput_(specialContainer, Feature.STORED, FEATURE,
-        shakaDemo.MessageIds.STORED_SEARCH);
+        'Filters for assets that have been stored offline.');
     this.makeBooleanInput_(specialContainer, Feature.ADS, FEATURE,
-        shakaDemo.MessageIds.AD_SEARCH);
+        'Filters for assets that have advertisements.');
     this.makeBooleanInput_(specialContainer, Feature.AUDIO_ONLY, FEATURE,
-        shakaDemo.MessageIds.AUDIO_ONLY_SEARCH);
+        'Filters for assets that do not have video streams.');
     this.makeBooleanInput_(specialContainer, Feature.THUMBNAILS, FEATURE,
-        shakaDemo.MessageIds.THUMBNAILS);
+        'Filters for assets that have a thumbnail track.');
     this.makeBooleanInput_(specialContainer, Feature.LCEVC, FEATURE,
-        shakaDemo.MessageIds.LCEVC);
+        'Filters for assets that have an LCEVC enhancement layer.');
     this.makeBooleanInput_(specialContainer, Feature.LOW_LATENCY_STREAM,
-        FEATURE, shakaDemo.MessageIds.LOW_LATENCY_STREAM);
+        FEATURE, 'Filters for assets that have a low-latency stream.');
 
     container.appendChild(this.resultsDiv_);
   }
diff --git a/demo/tooltip.js b/demo/tooltip.js
index 4ddb7a4f5..83b806cd6 100644
--- a/demo/tooltip.js
+++ b/demo/tooltip.js
@@ -7,19 +7,17 @@
 
 goog.provide('shakaDemo.Tooltips');
 
-goog.requireType('shakaDemo.MessageIds');
-
 /**
  * Creates and contains a tooltip.
  */
 shakaDemo.Tooltips = class {
   /**
    * @param {!Element} labeledElement
-   * @param {shakaDemo.MessageIds} message
+   * @param {string} content
    */
-  static make(labeledElement, message) {
+  static make(labeledElement, content) {
     tippy(labeledElement, {
-      content: shakaDemoMain.getLocalizedString(message),
+      content,
       placement: 'bottom',
       arrow: true,
       animation: 'scale',
diff --git a/demo/visualizer.js b/demo/visualizer.js
index a2e2ecdea..dbc5c6888 100644
--- a/demo/visualizer.js
+++ b/demo/visualizer.js
@@ -84,8 +84,7 @@ shakaDemo.Visualizer = class {
     inputContainer.addRow(null, null);
     this.screenshotButton_ = document.createElement('button');
     inputContainer.latestElementContainer.appendChild(this.screenshotButton_);
-    this.screenshotButton_.textContent = shakaDemoMain.getLocalizedString(
-        shakaDemo.MessageIds.VISUALIZER_SCREENSHOT_BUTTON);
+    this.screenshotButton_.textContent = 'Take Screenshot';
     this.screenshotButton_.classList.add('mdl-button');
     this.screenshotButton_.classList.add('mdl-button--colored');
     this.screenshotButton_.classList.add('mdl-js-button');
@@ -94,11 +93,10 @@ shakaDemo.Visualizer = class {
       this.takeScreenshot_();
     });
 
-    inputContainer.addRow(
-        shakaDemo.MessageIds.VISUALIZER_AUTO_SCREENSHOT_TOGGLE, null);
+    inputContainer.addRow('Take Screenshot On Stall', null);
     /** @private {!shakaDemo.BoolInput} */
     this.autoScreenshotToggle_ = new shakaDemo.BoolInput(
-        inputContainer, shakaDemo.MessageIds.VISUALIZER_AUTO_SCREENSHOT_TOGGLE,
+        inputContainer, 'Take Screenshot On Stall',
         (input) => {
           this.takeAutoScreenshots_ = input.checked;
         });
diff --git a/demo/visualizer_button.js b/demo/visualizer_button.js
index ddecba120..e2c706747 100644
--- a/demo/visualizer_button.js
+++ b/demo/visualizer_button.js
@@ -7,8 +7,6 @@
 
 goog.provide('shakaDemo.VisualizerButton');
 
-goog.require('shakaDemo.MessageIds');
-
 /**
  * A custom UI overflow button, to allow users to show the visualizer.
  * This cannot actually extend shaka.ui.Element, as that class does not exist
@@ -41,6 +39,7 @@ shakaDemo.VisualizerButton = class extends shaka.ui.Element {
     label.classList.add('shaka-overflow-menu-only');
     this.nameSpan_ = document.createElement('span');
     label.appendChild(this.nameSpan_);
+    this.nameSpan_.textContent = 'Buffer Visualizer';
 
     /** @private {!HTMLElement} */
     this.currentPipState_ = /** @type {!HTMLElement} */ (
@@ -57,24 +56,6 @@ shakaDemo.VisualizerButton = class extends shaka.ui.Element {
           !shakaDemoMain.getIsVisualizerActive());
       this.setIcon_();
     });
-
-    this.eventManager.listen(
-        this.localization, shaka.ui.Localization.LOCALE_UPDATED, () => {
-          this.updateLocalizedStrings_();
-        });
-
-    this.eventManager.listen(
-        this.localization, shaka.ui.Localization.LOCALE_CHANGED, () => {
-          this.updateLocalizedStrings_();
-        });
-  }
-
-  /** @private */
-  updateLocalizedStrings_() {
-    this.nameSpan_.textContent = shakaDemoMain.getLocalizedString(
-        shakaDemo.MessageIds.VISUALIZER_BUTTON);
-    // TODO: Make sure that the screenreader description of this control is
-    // localized!
   }
 
   /** @private */
diff --git a/test/demo/demo_unit.js b/test/demo/demo_unit.js
index 6f078ee0f..8c51b4355 100644
--- a/test/demo/demo_unit.js
+++ b/test/demo/demo_unit.js
@@ -33,22 +33,6 @@ describe('Demo', () => {
     await shakaDemoMain.cleanup();
   });
 
-  it('has all messages defined', async () => {
-    const englishBuffer =
-        await shaka.test.Util.fetch('/base/demo/locales/en.json');
-    const englishMessages = JSON.parse(shaka.util.StringUtils.fromUTF8(
-        englishBuffer));
-    const sourceBuffer =
-        await shaka.test.Util.fetch('/base/demo/locales/source.json');
-    const sourceMessages = JSON.parse(shaka.util.StringUtils.fromUTF8(
-        sourceBuffer));
-
-    for (const id of Object.values(shakaDemo.MessageIds)) {
-      expect(englishMessages[id]).withContext(`id=${id}, English`).toBeTruthy();
-      expect(sourceMessages[id]).withContext(`id=${id}, source`).toBeTruthy();
-    }
-  });
-
   describe('config', () => {
     it('does not have entries for invalid config options', () => {
       // We determine whether a config option has been made or not by looking at