.. and maybe other platforms as well (though X11 was not affected)?
The issue was that passing a higher resolution than the current desktop
resolution to SDL_CreateWindow() with SDL_WINDOW_FULLSCREEN didn't switch
to that resolution (even though it did switch to lower resolutions).
When creating a fullscreen window, window->fullscreen wasn't even set
at all (only zeroed out), setting it only happened if the user explicitly
called SDL_SetWindowDisplayMode(). So without that, SDL_CreateWindow()
-> SDL_UpdateFullscreenMode() -> SDL_GetWindowDisplayMode() used the
resolution from window->windowed.w/h which were limited to the desktop size
due to some weird combination of WIN_AdjustWindowRectWithStyle() and
WIN_WindowProc() being called after a call to SetWindowPos().
fixes#3313
Simple DirectMedia Layer is a cross-platform development library designed
to provide low level access to audio, keyboard, mouse, joystick, and graphics
hardware via OpenGL and Direct3D. It is used by video playback software,
emulators, and popular games including Valve's award winning catalog
and many Humble Bundle games.
More extensive documentation is available in the docs directory, starting
with README.md