Hello! Today my editor get a big bug. I think this appeared after I add new c++ file. I clear that file but get nothing. Half of blueprints was blank. I delete temp folders (Binary, Build, Intermediate, Saved) - rebuld project and blueprints get work. But all my material instant assets and animations is empty! Reset Layout don’t help. 
I find my problem. One plugin crash editor and all windows, remove it from project help me. Close this thread please.