Plex keeps 1 set of release notes per version (e.g. 1.40.5). Individual builds usually just change/add a few lines to that.
Most of the time you won’t notice this as there’s only 1 public release per version. With 1.40.5 there’s been one extra build released after that version was made available publicly. The later submissions was patching a vulnerability in the version of ffmpeg used by PMS.
You can see the differences per built highlighted in the release announcements (newly added/fixed scope is listed in bold).
