Noticed a weird UI bug on iOS recently. My game uses BIRP, Forward-rendering. One camera draws the background (solid color clear, no culling mask), one draws the scene (depth clear, culling mask does not include UI layer), and one is activated only occasionally to draw the floating paper airplane control (depth clear, culling mask does include UI layer).
UI mask works correctly when the third camera is disabled:
But UI mask breaks when the third camera is enabled:
Repros only on iOS devices, tested on iPhone 13 mini and iPad mini 6 (iOS v 17.6.1), and built using Unity 2021.3.41f1 and Unity 2021.3.43f1. Haven’t gone back to determine which version this started with but it is fairly recent.
May or may not be related to this bug on macOS that likewise caused undesired visual artifacts while this camera was active.