Specify the CSS selector used for the "default" window/canvas.
Defined in <SDL3/SDL_hints.h>
#define SDL_HINT_EMSCRIPTEN_CANVAS_SELECTOR "SDL_EMSCRIPTEN_CANVAS_SELECTOR"
This hint only applies to the emscripten platform.
The default value is "#canvas"
This hint should be set before creating a window.
This hint is available since SDL 3.1.3.