Just tried it and it works well, it seems that it is similar issue with what I experienced last week. It was not login issue, but logged out issue although it is not happening anymore. What browser did you use?
Edit:
After replied to your post and back to the browser tab where I visit FJ, my account is logged out already. It seems that my previous issue is coming back.
I use firefox , support asked me to clear cache but that didn't solve the problem
they asked me to use chrome and same happened , but few minutes later I tried again with chrome and I was able to log in
the weird thing is that firefox still not working for me at the moment even after clearing cache , and I haven't changed anything in chrome so IDK how it was fixed