I don't understand wtf just happend but after a couple of minutes and a browser refresh everything is back to normal and all styles are being applied again...
So I don't think I need to post the logs... Now I have just the problem with the Integrity Check...
I just updated to the latest version but I now have the problem that after loggin in I don't have any style... Everything is just white and I also don't have any icon images? Does someone now a solution for this?