User profile activity empty, sign-in autofill broken, can't sign out

Gosh, another broken forum feature.

Under my user profile, my "My Activities" is empty. I'm sure I've posted here a few dozen times, with equally frustrated posts. Now they're gone.

Hmm, maybe I accidentally signed in under the wrong profile? That's possible since apparently login autofill isn't working on this website anymore.

Ok, I'll sign out and back in again. Oops! Can't sign out.

Good lord. This place keeps getting worse.