Local Multiplayer Shared Camera UI Not Visible

I am making a game with local-multiplayer that uses a single camera (not splitscreen, think Super Smash Brothers). I want ANY one of the players to be able to pause the game and navigate the UIs. When the primary player pauses the game, everything works fine, but when player 2 pauses the game, the UI is invisible. Focus is removed from the game viewport, as if there’s a UI to focus on, but nothing actually appears on the screen.

I enabled splitscreen just to test, and everything worked fine for every player - it’s only a problem when using a shared camera.

I am adding the UI to the screen by calling AddToPlayerScreen(Priority) on the root-widget in code.