>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?

[0] https://en.wikipedia.org/wiki/Scunthorpe_problem

Somebody probably put in a regexp with .mov$ , however for regexps the dot (.) matches everything (and $ matches end) so the i in asimov is eaten regardless and then the rest of the match succeeds.

You can see the fix they made in the linked MR.

It wasn't a regex, they just did a generic "ends with" check.

Perhaps the sub-clause is redundant there?

'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".'

>'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.

That was before the fix.