There's not much you can do about this I'm afraid. The boolean controls if Phaser will still update when the browser fires a visibility change (i.e. giving focus to another app), but what happens when you change tab is different, it's the browser deciding to no longer fire requestAnimationFrame events, consequently pausing your game (even though Phaser itself never thinks it has paused, it just never gets its core loop called because rAf has been halted).   Not all browsers do this (although mos