For a multiplayer game with 2 players,
Invitation is sent using GKMatchmakerViewController.
Other side recieves the invitation and launches GKMatchmakerViewController using initWithInvite.
Both sides show connecting... label.
Prior to iOS 13.4 -
connecting label is changed to accepted,
delegate method matchmakerViewController:didFindMatch is called on both sides and the game starts.
iOS 13.4 - both sides are stuck with the connecting... label,
delegate method matchmakerViewController:didFindMatch is never called so the game never starts