No Save Button in Microsoft Edge

Hi all!

Strange problem: if I am trying to password-protect a review in Microsoft Edge, the modal does not display either Cancel or Save buttons (see screenshot). They are just plain missing. 

So every time I need to password-protect a review (which is every time I make a review, this is a policy issue) I have to do that in Chrome which has the buttons. Weird. Any ideas why that should be the case?