So You are running Minecraft in fullscreen / windowed.

you tab out game/minimize it, Then tab in game again & you'll have Black screen IF ray tracing is turned on. meaning that it only affects ray tracing.

this is a critical issue as tabbing out/in game is very common, I currently don't have acess to an evidence image, but It's black screen with UI there only, always reproducible & takes a few seconds to do.

hope I explained everything.

UPDATED INFO: Engine switches to DX11 after minimizing and reopening the game, causing DXR to stop working