I'm using the Sony WH-1000XM3 on Ubuntu 20.04. The headphones support media controls through touch gestures. Volume up/down works fine, but pause/play and next/previous track does nothing. Neither in Spotify nor on YouTube.
I tried to set Settings > Keyboard Shortcuts > Sound and Media > Play (play/pause) to "Audio play" etc but that made no difference.
I noticed that using they headphones media keys don't show anything when running xev in Terminal.
Any ideas how this can be resolved?