The player video surface is a single shared MPVOGLView that is re-parented
between the mini-bar container (main window) and the expanded-player sheet
(a separate sheet window). When presenting the sheet, the new container
attaches the shared view before the old mini-bar container tears down, so
the old container's viewWillMove(toSuperview: nil) was ripping the shared
view out of its new home via removeFromSuperview() — leaving it with no
window and a black surface. Symmetric, so it also blanked the mini-bar
preview after collapsing.
Only detach the shared view if it still belongs to the container
(superview === self). Also force a repaint on window reattach so a paused
frame redraws, and extend the onAppear resumeRendering to macOS.
MPVOpenGLLayer called fatalError() when CGLChoosePixelFormat failed for
both the 10-bit and 8-bit (kCGLPFAAccelerated) formats, killing the app at
launch on machines without a usable GPU such as virtual machines.
Add a non-accelerated software pixel format as a last resort and make the
whole OpenGL init path failable: createPixelFormat/createContext return nil
(with an error log) instead of aborting, MPVOpenGLLayer.init becomes init?,
and MPVOGLView holds an optional layer, throwing openGLSetupFailed from
setup(with:) when OpenGL is unavailable. That error is already handled by
MPVBackend.setupMPVAsync, so the app now launches cleanly and only logs that
video playback is unavailable.
