Major changes in 3.12.1:
- Bump required versions of grilo and GStreamer
- Fix delete button's initial state
- Switch to the player view quicker
- Add support for starting a playlist paused
- Escape selection mode when pressing Esc
- Fix shuffled items starting to play in random order
- Hide popups when leaving the window, but not when a popover
  (volume, menus) is visible
- Don't toggle popups on touchpad clicks, just on touchscreens
- Fix scroll-wheel going forward 2 minutes instead of 1
- Save the downloaded subtitles in the video directory
- Re-add drag'n'drop support for the video widget