The changelog can be obtained A) at reaper.fm/whatsnew.txt B) from whatsnew.txt file which comes with the REAPER install, or C) within REAPER via Help -> Check for new versions of REAPER.
Note: The formatted changelog needs proofing due to possible duplicates in different meta categories and appearence of non-categorized change descriptions in the meta category OTHER, which nevertheless still may fit any of the meaningful meta categories. In these cases refer to the Keyword Classification Legend below to determine whether the change description fits the meta category it has been placed under. Change descriptions containing links to forum posts/threads may refer to actual bug fixes despite lack of keywords relevant to BUG FIXES meta category. So these need to be double checked if maximum accuracy is desired. If you encounter duplicates in meta categories other than REGRESSIONS or have a suggestion for new keywords please submit a bug report / feature request or a pull request so this can be addressed.