User mentions not working for usernames ending in `_`
User mentions that end in _
are not getting translated in to user mentions.
For example, @mpeychet_
gets rewritten to @mpeychet\_
by the autocompleter. This then triggers our new code introduced by !45922 (merged) which honors markdown escaping.
Unclear if the autocomplete has changed, or if it's just from the new markdown MR