I disagree with the recent cooplaints about the abuse of Soapbox's shameful lack of any reasonable external input validation.
Anyway, it looks like Poa.st has Nichy's patch. The test just showed up like anywhere there. I checked another random Bopesox and it doesn't, so they'll see a different message near the top of this post (check the source), and this paragraph won't show up. (I think Bopesox should just merge Nichy's patch. I don't know what happens with Akkoma.) Anyway, not all instances validate user input, and you can't rely on external validation of input. So FSE doesn't drop that class any more. If you treat any facet of external input as trustworthy (other instances are external), you will get bugs like this one.
If I have fucked anything up, I'm not fixing it, because I'm going to eat shortly. (Look at the source of this post if you don't get the joke.)
Thank you for reading my blog post about your mom.