forum layout completely changed

The site suddenly has a vBulletin format which can't be changed.
Everything that was convenient (newest threads overview on the right side, users online, threads statistics below, latest posts etc) is gone.
You can't see ANYTHING anymore except the thread title.

What's this? Makes the forum completely unusable.

update: nevermind. It's suddenly back to normal (I didn't do anything).
Weird stuff.

Mine switches to mobile view on my laptop a lot, and right now my language is in german altho I didn't switch anything. I think the forum host is screwy