Thanks @seancorfield... indeed I had forgotten that I had added that extension. Oddly, those messages do not contain anything like the syntax for wrapping LaTeX, so this is simply a bug.
@blak3mill3r Yeah, I wrestled with it for a while. Changing the delimiters improved some messages but broke others. So I just gave up and figured I didn't need math notation enough to put up with the bugs 😞
Ah, well. I thought the browser extension was a nice idea in lieu of Slack supporting it
maybe some day