[kwlug-disc] Can flip desktops when screen sharing (at least in BBB)

[Mikalai Birukou]

Turn on BBB presentation, share screen (not a single window), and viewer 
of a BBB stream will see correct changes.

We can use it in presentations: one desktop with slides, another with 
demo part one, and so on, add as needed.

While presenting, when you don't have two screens in front of you for 
prepped material, the only screen better be a mirror of what audience 
sees. Twisting once head to look at other monitor adds a tiny bit 
disorienting friction. Hence, use multiple (virtual) desktops, flip 
through them in front of the audience. Prepped table of a surgeon is 
also an impressive sight. And splitting material into "desktop pages" 
will also structure a presentation.

I suspect/hope that mac and windows should also pass desktop flips on 
shared screen.