I first noticed this happening yesterday (May 5, 2019) and it persists. During playback, the background, album art, player controls, notification bar (clock included)... everything... disappears and all I see is a solid black screen and the chosen visualization. If I tap anywhere on the screen, everything comes back as it should and after the preset time, everything disappears again and it's back to a black screen with the visualization. I attached a screenshot of what I see.
I hadn't changed any of the settings so I have no clue what's going on or why it just started yesterday but though