Picture-in-picture: multiple simultaneous PiPs?
Is it possible to have several PiPs running simultaneously in separate 'windows'?
The PiP view is actually really useful just for losing all the window decorations - panels, info/status/bookmark/title/tab bars etc.
It would be useful to be able to pop out two, three or more different videos (e.g. multiple youtube videos) to arrange them around the screen with optimal scaling/space usage to fit them all in.