Edit, found the problem, it’s not EE, it’s my browser Chrome that is deleting those parts.
Weeeeird, I’ll try finding out what the heck that is about….
Oh, it’s even deleting stuff I typed in this post, URL’s and other random stuff that it doesn’t like apparently, hmmm…
Ok I found the Evil extension that was causing this, it’s named Linkification, it makes non-clickable links clickable, and as a bonus feature it deletes stuff in textareas apparently.