But the in the screen capture of article, the user name is actually 'issac.asimov', i.e. the mime type does not immediately follow the dot.
A variation on the Scunthorpe Problem[0] then, eh?
It wasn't a regex, they just did a generic "ends with" check.
'The problem was named after an incident in 1996 in which AOL's profanity filter prevented residents of the town of Scunthorpe, Lincolnshire, England, from creating accounts with AOL, because the town's name contains the substring "cunt".'
Right. Regardless of the specific pattern matching function, in both cases, the results were both incorrect and unwanted. Which is why I consider this instance to be a variation on the same issue.