Replying (in a MR) to a comment which was made on a commit (which is part of that MR) is broken

Summary

If a comment is made in on a commit which is part of a MR that comment is also shown in the MR itself (e.g. "Eduard Braun @ede123 started a discussion on commit ead3bb11 about 17 hours ago").

GitLab offers to "Reply..." to this comment directly in the MR but this functionality is broken: After clicking the "Comment" button the message disappears but is never added as a comment to the commit in question.

Example Project

Just tried to answer a commit comment in inkscape/inkscape!48 (closed) which failed.