URL of commit link is different in preview and published post

Summary

A commit sha in a comment is automatically turned into a link. In a MR comment, the URL becomes [project_url]/merge_requests/[MR_id]/diffs?commit_id=[sha], but when editing and previewing the comment, the URL shows as [project_url]/commit/[sha].

Steps to reproduce

Write a commit sha in MR comment. Before publishing (or after, by editing it), click on "Preview", note the URL the generated link points to. After publishing, note the URL of the link again.

Example Project

https://gitlab.com/Jellby/test/merge_requests/17

What is the current bug behavior?

The links are different, which means the preview is wrong.

Another question is which of the two links one actually wants. Personally I want the vanilla commit, not the MR diff...

What is the expected correct behavior?

I expect the preview to show the same link that will be in the final post, that's one of the purposes of the preview.

I'd also like a way to get the link to the bare commit.

Output of checks

This bug happens on GitLab.com