I have tried these alternative methods for putting in the names. Sometimes they work, sometimes they don't. I noted the dropdown box as something that seemed related to the issue, and thus if I could find a simple reason why the browser wasn't running that script or whatever it would be a quick fix.
In any case, I will not be pressuring anyone to change their forum name(s), I mostly raised the issue in the hopes of not having to do so at all. With luck it will be a transitory.
A quick test suggests Chrome is functioning though, so I will probably just use it instead when needed.
Thank you to everyone who gave advice on this subject.