I believe current behavior is correct. +Zach for confirmation.

assigned to zalcorn@ for behavior conformation. Please assign back if it needs the change.

We aren't able to do this reliably without MediaSession for Chrome Desktop. I believe this is being looked into for 2018.

zalcom@, what do you mean exactly? It would be possible to pause running playback. The issue I guess would be that resuming would require to resume all the playbacks that were previously played. I agree that waiting for audio focus on desktop would be easier. Though, is what I mention above the actual reason?

If we plan to do this at some point, mind keeping this open and marking it as blocked on the bug that tracks adding the functionality that's needed?

I think that there's a bigger question about whether it makes sense to pause everything the first time the key is pressed and not do anything when it's pressed again, though. If this key starts affecting unfocused tabs, there are lots of weird corner cases. I'm having a hard time thinking of ways to prevent this from being confusing to users.

Code entry is here: https://cs.chromium.org/chromium/src/chrome/browser/ui/ash/media_client.cc?type=cs&q=handlemediaplayp&sq=package:chromium&l=168

It is possible to pause all unfocused browsers/tabs. If this is what we want, we then need to guarantee correct resuming I think, as in #5.

Re #6, if not doing anything when it's pressed again, it doesn't sound like play/pause key but just pause key.