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src/Uuid.php

@@ -488,7 +488,8 @@ class Uuid implements UuidInterface
      *     address
      * @param int|null $clockSeq A 14-bit number used to help avoid duplicates
      *     that could arise when the clock is set backwards in time or if the
-     *     node ID changes
+     *     node ID changes (in a version 2 UUID, the lower 8 bits of this number
+     *     are replaced with the domain).
      *
      * @return UuidInterface A UuidInterface instance that represents a
      *     version 2 UUID