Interesting, that's different from what Safari supports (see sibling comment). I wonder what the algorithm is to generate a good password that matches a given

Interesting, that's different from what Safari supports (see sibling comment). I wonder what the algorithm is to generate a good password that matches a given regex. Also there's a potential problem with patterns that are wrong or contain errors, that may result in simple and insecure passwords. I don't see how Mozilla's approach is better than Safari's.