allow several people to share their screen at the same time during a collaborative conf call in a bubble / collaborative whiteboard / overlay pencil

With covid 19, we are remote working much more. Some tasks we do are not only presentation from one manager to employees.

For example brainstorming, what i usually see right now is that the one with an idea has to share his screen to expose it, then when someone else has something to say it cannot easy interact with the first one screen. He usually got tired to explain with words what he wants to say and end by asking to share his own screen.

The screen sharing then slowly goes from people to people and not really help to do a collaborative task.

This process is little annoying, people would sometimes prefer to share their screen the same way we share the webcam. (mozaic, ability to focus on one screen fullscreen, ...)

I also know that there are some online collaborative whiteboards, with the capability to share a drawing board like a teacher using markers in classroom.

I agree with the fact that the shared result shall be modified only by one people at a time (in classroom you only have a single marker) but handing over markers has to be quick.

Still this solution means that we use 2 services, one for the collaborative and one for the voice.

Maybe support of a basic collaborative whiteboard or integration of an existing whiteboard could do the trick.

Or at least the possibility for a "student" (a listener) to "go to the whiteboard" (the shared screen of the bubble) and interact with it with "a marker" (the mouse) on an overlay layer shared with everyone.

expected actions could be: visible mouse position to show what you point, clic to draw overlay to circle or underline things, overlay highlighter marker, overlay text writing.

and controls like save overlay pic, erase overlay, undo, redo, ....

maybe for change the overlay you need to own the marker and hand over someone who request it, but everyone can always show things with their mouse (meaning you have several mouse pointers in the overlay)

The idea is to make the thing interactive enough to avoid using another whiteboard tool.

Thanks