That might be it, I usually have a default password length in the 70s. I'll try that after work and see what happens
Update: This actually worked. I was able to log in on Firefox by copy/pasting, changed my password to under 60 characters, and now I can log in everywhere without a problem. There's a chance it was a coincidence, since I hadn't tried logging in for a day or so, but it's definitely working now. Thanks for this; I never would have thought of it on my own.