I see your point. But that would only be the case if one wants to show the same UI at the same time in both - the video-overlay and the panel, right?
Or are you talking about an extension that can either be shown in panels or as a video-overlay?
But that is not really the goal I would like to achieve having these two screen spaces. Also the examples I mentioned do not share any UI controls at all.
Surely there has to be some kind of synchronisation between the panels at the data level, but that has to be done across different viewers anyways (e.g. using a secure WebSocket connection to an EBS).
It’s more like a split-up UI that I’m talking about. Like e.g. in car, where there could a) be a speedometer behind the steering wheel and b) a bigger screen with other information in the center console which is better fit there. These two would be the video-overlay (e.g. viewer_videooverlay.html) and the panel below (e.g. viewer_panel.html), respectively.
It’s just about the broadcaster not having to install “two separate” extensions when it’s actually just one (with one config panel).