The gif raw data decoded by stb decoded and ffmpeg are different

[Adonis-Song]

Hello. I want to use stbi decode this gif.
test_data.zip

The image decoded by stb and ffmpeg is as follow.

The Image decoded by stb used last frame as background, and ffmpeg not.

After debug code , I find these code in stb. When dispose equal two, it will use last frame as background ,but ffmpeg wont. In the documentation of gif dispose equal two mean restore to background color.

stb/stb_image.h

Lines 6808 to 6824 in ae721c5

	if ((dispose == 3) && (two_back == 0)) {
	dispose = 2; // if I don't have an image to revert back to, default to the old background
	}
	if (dispose == 3) { // use previous graphic
	for (pi = 0; pi < pcount; ++pi) {
	if (g->history[pi]) {
	memcpy( &g->out[pi * 4], &two_back[pi * 4], 4 );
	}
	}
	} else if (dispose == 2) {
	// restore what was changed last frame to background before that frame;
	for (pi = 0; pi < pcount; ++pi) {
	if (g->history[pi]) {
	memcpy( &g->out[pi * 4], &g->background[pi * 4], 4 );
	}
	}