on screen share I lose my camera window: it goes black

[bud oracle]

How do I toggle it back

[Tibbi Scott]

I had the same problem earlier today on a hangout.  Later on another hangout I didn't.  There was an update today.  Maybe that had something to do with it.  Maybe try leaving the hangout, clearing the cache.  and restarting the browser.  Sometimes problems will clear up that way.