Click on a release to see all issues within it, which can either be Open (meaning they are in-progress for that release) or Closed (meaning they are done).All changes for GameMaker versions are listed on GitHub. The linked page lists all major releases for GameMaker.
There are two categories of releases: Open (in-progress or future release) and Closed (released to public).
Click on "X Closed" to see the released versions:
Click on a release to see all issues within it, which can either be Open (meaning they are in-progress for that release) or Closed (meaning they are done).
If a version is in its beta period, the Closed issues have likely made their way into the latest beta release, or will go in the next beta update.
The GitHub issue lists are always up-to-date, so it's a good place to check for known issues before reporting something.
GitHub only contains changes for GameMaker 2023.8 and above. Release notes for older versions are available here: IDE / Runtime