Events polled via SDL_PollEvent temporarily have type SDL_KEYUP and SDL_GetModState loses modifier while key is continuously pressed

[janmarti3]

While having e.g. left-Ctrl continuously pressed, it can be observed that the function SDL_PollEvent generates SDL_EventType::SDL_KEYDOWN events with SDL_GetModState returning SDL_Keymod::KMOD_LCTRL as expected. However, at random intervals, for just one cycle, it unexpectedly generates an SDL_KEYUP event with SDL_GetModState returning KMOD_NONE and therefore temporarily loses the actual state.

SDL Version: 2.28.2, System: Ubuntu 22.04.5 LTS