This is nice. Somewhat related, I've been using this free, open-source app called BeardedSpice[0]. It solves my pet peeve of the media key doesn't always control the right app/browser tab.
> BeardedSpice is a menubar application for Mac OSX that allows you to control web based media players and some native apps with the media keys found on Mac keyboards. It is an extensible application that works with Chrome (Canary, Yandex, Chromium) and Safari, and can control any tab with an applicable media player.
> BeardedSpice is a menubar application for Mac OSX that allows you to control web based media players and some native apps with the media keys found on Mac keyboards. It is an extensible application that works with Chrome (Canary, Yandex, Chromium) and Safari, and can control any tab with an applicable media player.
[0]: https://beardedspice.github.io