SDL clipboard text is not cleared when clipboard data is set by another program

[po-87]

After copying some "data" in another program, so that SDL_HasClipboardData becomes true, I still get the old clipboard text from SDL_GetClipboardText(). The clipboard text is not cleared until after I have called SDL_GetClipboardData.

System:
Debian 11 with the MATE desktop environment (X11).

The Program:

#include <SDL3/SDL.h>
#include <stdbool.h>

void log_clipboard() {
	SDL_Log("\tClipboard text: %s", SDL_HasClipboardText() ? SDL_GetClipboardText() : "no clipboard text");
	SDL_Log("\tHas clipboard data? %s", SDL_HasClipboardData("image/png") ? "true" : "false");
}

int main(int argc, char *argv[]) {
	SDL_Init(SDL_INIT_VIDEO);
	SDL_Window* window = SDL_CreateWindow("", 300, 200, 0);
	bool quit = false;
	while (!quit) {
		SDL_Event event;
		while (SDL_PollEvent(&event)) {
			if (event.type == SDL_EVENT_KEY_DOWN && event.key.key == SDLK_V) {
				SDL_Log("Before calling SDL_GetClipboardData:");
				log_clipboard();
				
				size_t len;
				SDL_GetClipboardData("image/png", &len);
				
				SDL_Log("After calling SDL_GetClipboardData:");
				log_clipboard();
			}
			else if (event.type == SDL_EVENT_QUIT) {
				quit = true;
			}
		}
		SDL_SetWindowTitle(window, SDL_HasClipboardText() ? SDL_GetClipboardText() : "no clipboard text");
		SDL_Delay(20);
	}
	SDL_Quit();
}

Steps to reproduce the problem:

1. Copy "some text".
2. Start The Program.
3. Copy some "data" in another program (e.g. by selecting part of an image in GIMP or Krita and press Ctrl+C).
4. Make sure The Program has focus and press V.

Expected output:

INFO: Before calling SDL_GetClipboardData:
INFO: 	Clipboard text: no clipboard text
INFO: 	Has clipboard data? true
INFO: After calling SDL_GetClipboardData:
INFO: 	Clipboard text: no clipboard text
INFO: 	Has clipboard data? true

Actual output:

INFO: Before calling SDL_GetClipboardData:
INFO: 	Clipboard text: some text
INFO: 	Has clipboard data? true
INFO: After calling SDL_GetClipboardData:
INFO: 	Clipboard text: no clipboard text
INFO: 	Has clipboard data? true