Locked all elements on screen.. and I can't unlock?

Hi there,

I have an issue: I have a screen designed with many elements on it, and somehow I managed to lock all of them. It’s for me unclear to see which element is locked and which is not. Right-mouse click > unlock often doesn’t unlock the element I’m trying to unlock.

Is there a way to ‘unlock all’ elements? Or just unlock everything?
Or any other suggestion?