Screen disappears when focus lost during fullscreen

[bentley]

Running mupen64plus-2.5.9 on OpenBSD -current.

I have a dual screen setup. If I run a game fullscreen or windowed, it generally plays just fine.

In fullscreen mode, if I move the mouse to the other (non‐mupen64plus) screen, mupen64plus’s graphics output disappears completely, and I can see and interact with the windows behind it. The game continues to play in the background (evidenced by the audio, anyway). I can’t find any way to get the window back. There’s no additional output in the terminal window, except for normal gameplay messages (“Initializing SDL audio subsystem,” etc.).

Nothing of the sort happens in windowed mode; I can move the cursor anywhere with no repercussions.

Tested with both glide64mk2 and rice, with identical results.