I downloaded TBird 78.6.0 and extracted it to a directory under my home directory. The ptofile had previously run under 78.4.3, but when I opened it under 78.6.0, it created yet another *NEW* profile. This is just a point release, not a major breakage release. Just why is it creating new profiles?

Sure, I can hack up a workaround and beat it into submission, but I shouldn't have to. It's just a point release, there's no reason for it to yet again break my profiles. It seems the devs think people are just running single-accounts with no customization. But it's specifically because we have complex configurations that we are using a REAL email client (a web browser is NOT an email client). So stop breaking the only remaining usable email client.