Media controls default to last focused window that plays media.

[Kroooza]

Currently if i open a youtube video in firefox, then pause it and open spotify, when i use the media controls on my keyboard they control the youtube video. This is just one example, but i find it quite annoying how when i have 2 media playing applications open at once the media controls default to whichever one was open first. Please make it default to last focused window that plays media, and ideally add a way to change it, since linux is all about customization.