[Crowdicity: Full controls on Picture in Picture mode window, 109 votes atm, "Mozilla developing"]
Currently PiP window can only offer 3 buttons (4 if you turn on the mute button in config). Additionally it can rewind videos, but you can only do that with arrow buttons.
It would be a lot more intuitive if PiP window provided an interface, similar to default browser video control panel with a few additions
My concept is on the screenshot, where
Top elements have some space between them and edges so you are able to use this space to drag the window too (aside from area in the middle). Black bars on the screenshot are a part of video, but for videos without them, top elements, when shown, would have soft shading (to be able to see them).
There's also a discussion, created by Mozilla team about this and other video features:How can we make video experience in Firefox better for you?