Merge request Commits and Changes tabs do not work

After upgrading my 9.2.x installation to 9.4.3, I’m seeing a peculiar issue where the “Commits” and “Changes” tabs of a merge request show up empty.

If I query the diffs page directly as such:
Then I do see correct HTML output.

I’ve tried/verified the following:

  • The command rake gitlab:check shows up all-green.
  • Running rake yarn:install gitlab:assets:clean gitlab:assets:compile cache:clear does not resolve the issue.
  • The issue persists between different browsers
  • The issue applies both to new merge requests and existing ones.
  • The production.log, application.log and sidekiq.log do not show any errors.

I’d be more than happy to provide logs and further system information, but I’m not quite sure where to start debugging this issue.

Any help or pointers are greatly appreciated!