The awesome trick for adding a thumb to a simple mp4 video with ffmpeg works perfectly, until I took an mp4 with chapters in it. The thumbnail is added, but the output file can't be played on many devices. This command didn't work as required:

ffmpeg -i video.mp4 -i image.png -map 1 -map 0 -c copy -disposition:0 attached_pic out.mp4

What can be wrong and how to do it right?