Also getting "unexpected internal error" on both PC-NA and PC-EU. Tried restarting Steam a couple times, tried restarting my whole computer. Can't use the help.elderscrolls.com website because dark theme gives me a migraine (no this is not up for debate) and there's no reader mode setting.
I cant log in on my main account. Login failed. Username/ password may be incorrect or inactive try steam. I can however log in to my alt account. very strange.