Extension to popular browsers at least Firefox to handle multimedia keyboard keys?

Question

Browsers

When listening to music on countless online players, I personally lack only one feature - the ability to control music playback using multimedia keys - namely pause / play / next.
It is clear that it is unrealistic to automatically support all the variety of html players, but some primitive semi-auto-configuration would be enough for me, such as poking the mouse into an area on the page and indicating which multimedia button it corresponds to.
I think if such a plugin does not exist in nature, then writing something like this is not difficult, the only question is how to catch multimedia button presses globally , incl. with an inactive browser window?

Answer 1

For Chrome, there is Sway.fm ( in the store ), a fixed, but rather wide set of sites is supported there, including VKontakte and Yandex.Music (UPD: and you can add it yourself, sources on github ).
For Firefox I'm currently looking and there seems to be no solution yet.

Answer 2

Although the question is old, but relevant, and in the issuance of Google is not far away.
Working extension under Win: https://addons.mozilla.org/en/firefox/addon/media-...