Until today it has always been the case that when you make a change to a mailbox be it a user or shared, you click save and you can move on to your next item rapidly. The window only stayed open if there was a problem that needed your attention.

Now, I get a confirmation window every time I save a change which is very unnecessary and adding inefficiency to an already-slower to manage system than an on-premise Exchange.

Please put it back to the way it was last week. If it ain't broke, don't fix it!