QVideoWidget and QMediaPlayer bugs

1º - Sometimes when changing the QVideoWidget to fullscreen and when the widget backs to normal the QMediaPlayer disappear and needs to play again, or resize the window in order to appear again.
2º - QMediaPlayer doesn't support subtitles.
3º - When the QVideoWidget is in fullscreen and you keep pressing tab it starts blinking (not a normal behavior), like if it were passing focus to other widget.
4º - When you press alt + tab when the QVideoWidget is in fullscreen you can't see the QMediaPlayer playing on the application, it popups out and only the controls remains.
5º - When you press alt + tab when the QVideoWidget is in fullscreen and you back to the application the QMediaWidget disappear. (unless you set QMediaWidget to QMediaPlayer::VideoSurface)
6º - QMediaPlayer doesn't play mkv files.
5º - If you play QVideoPlayer using the button (see Media Player Example), and pause, then go to fullscreen (double click or fullscreen button) and then back again, QVideoPlayer disappear. The same happen if you pause and maximize windows.