As was just brought up in the discussion about the vote, the current markdown-parsing in the comments is causing quite a few bugs and the associated convenience might not be worth the costs of the bugs. We now have an experimental option in your user-profile to switch to a pure markdown editor, so it might make sense to just remove the automatic markdown parsing from the comment editor and have it just be a pure rich-text editor.
I left two comments that you can vote on to decide between the options.
Like many others I have been annoyed by the bugs and the neither-one-thing-nor-the-other-ness of the WYSIsometimesWYG comment editor, but I'm still voting for this option. If we had non-WYSIWYG plus preview I might go the other way (but I'm not sure, because then the preview would take up space -- maybe put it in the margin?).
(This is a thing where if we had the sometimes-requested option to vote with less than the full weight conferred by karma, I might use it...)