Comments made from multiple browsers around the same time can show up in wrong order.
While commenting on gitlab-ce#34115 I briefly switched to my phone to test something and make a comment, then switched back to my computer to comment on the same issue, and strangely the second comment showed up first:

I am guessing this has something to do with the quick-submit feature we added having a race condition with our update polling. Perhaps we can manually check timestamps to ensure we insert notes and comments in the right order?
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