Yes, I have the same issue, only in Opera, on 4 devices. The fact that it's "only in Opera" is the signal that, if other browsers don't have this issue, it's fixable. It needs attention. The browser freezes, and you can't click on the browser back button, nor Allow/Deny.

Screenshot:

I did, however, find a workaround!
If I click on the device go-back buttton (not the browser button), then I can continue with the page I am trying to get to.