WP page editor doesn't work anymore

Can’t edit my pages anymore. After some plugin updates (just standard stuff like Akismet and SiteOrigin) the WP editor doesn’t work anymore. When trying to edit a page, it only shows an empty title box and an empty drop box called “name”, that’s it. The page content is not loaded at all fro editing.
Did anyone come across the same issue? There’s no fancy stuff on the website and I am a bit lost now after a more or less sleepless night……