What i noticed in Linux Mint is when loading a rom, it displays properly. When loading another rom on same instance it opens another “untitled window” (plus the Retroarch normal window) and black screen. When switch fullscreen/window then screen is back.
It’s version 1.22.1 there and Vulkan. It seems there were some changes in code since 1.21 or so that introduced all sorts of problems.
I cornered the issue somehow, black screen in next rom load when using ozone UI, when switch to xmb UI no black screen in Vulkan. Still opening another “untitled window” but no black screen.