The pause menu used to have a black tint. In Java Edition, the overlaid background is handled as a texture file that can be configured via resource packs.
Steps to reproduce:
Enable game pause in Settings -> General -> General -> Pause
Pause the game
Observed result:
The pause menu background is completely transparent.
Expected result:
The pause menu background is not completely transparent and has a black/gray tint, like in Java Edition.
I could confirm.