Steps to reproduce the issue
Enter the Play menu by hitting the button “Play” on the main menu.
Go back by either hitting the escape key or pressing the back button in the top left.
Visual artifacts appear on the transitioning screen and then disappear when the main menu pops up
Expected result
When going back to the main menu the “Play” menu slides to the right without leaving visual artifacts
Actual result
When going back to the main menu the “Play” menu slides to the right and leaves visual artifacts
This issue is being tracked at MCPE-188337.