It just didn't always behave and syntax highlighting didn't work at all sometimes; but it may have been that the system as a whole was misconfigured.

Mattermost CEO here, thanks for trying us out!

Would love to squash the bug for you, open to filing an issue?> https://github.com/mattermost/mattermost-server/issues/new

We used to send bug coins just for release candidates, but if you find a bug in production you get one too now: https://www.youtube.com/watch?v=7D6FJsdE_aY

Thanks for the response, we'll be sure to post anything that looks like a bug! At this point it's likely our operations team simply hadn't configured it correctly (it is a trial and not a production deployment).

Best regards to the team.