Can't disable default subtitle language in a video file. And some video player related [Feature Request]

[fossist]

When opening a multi (language) subtitle mkv video, it show default subtitles. Is it possible to include a option to select subtitle language? Until we have option to select subtitles, I think it would be better to disable the subtitles by default.

As this project uses mpv player as it's video engine, qimgv has potential to become a go to video player. I suggest these basic requirements: Make video seek bar of full width. It is easier to navigate long videos/movies. Option to toggle hq playback. It is on by default and it uses more cpu. (mpv player has this configuration option) Ability to add mpv configuration file. To change gpu settings and many more. It will open endless possibilities, but I don't know if it is an good idea or not.