Yep! No issues apart from, on MacOS, having to find all the places where the Categories and Primary Inbox are set, so I can turn them all back to how it was (i.e. off).Have you been finding the stock mail app to be working well in 18.4 b1?
I'm liking the new option to return to the mailbox after deleting a message rather than just opening (and marking as read) the next one.