Controls panel height is now 3px less then before (as intended). Change default window size setting to make it look good with 16:9 video on fresh install.
We cannot depend on the value saved by GStreamer, cause it is shared with all GStreamer based apps. Lets save the last value to gsettings instead to make sure this is the volume we used with this app. With this change we can also see the right volume on startup before media file is loaded (previously it was shown always as muted).
When dark theme is used, sliders (especially progress on fullscreen) tend to look a little too dark (as if they were disabled). To overcome this, add an option to force them to be 20% brighter.
The "vah264dec" plugin is a new and much better VAAPI implementation then default one in gstreamer-vaapi. Unfortunately as of now it works correctly only on Wayland and causes crashes on XOrg. Wayland users can easily enable it in video player preferences advanced tab settings to get improved performance and lower CPU usage.