It started a couple of hours ago while I was in the middle of a Legion event. Popped up three times asking for permission for Battle.net to make changes to the computer. Then it did it again when I was fighting the World Boss Avarice. Got me killed that time. When I signed out of Diablo 4, I had a error message on Battle.net say “oops” there was some sort of problem.
I noticed on the PC forum that there is a thread there with people posting about the same problem just recently starting for them too.