In G+ hangouts, I'm often sharing my desktop. Sometimes when I do this I mute the other participants because I'm giving some kind of lecture, but I will check back to see what they're saying in chat for questions.

When I do this, there's a hhhaaallllll ooofff mmmiiirrrrrrooorrrsss effect where my window is drawn inside itself down into infinity. It's very distracting and it stresses people out. :)

This isn't a problem if I'm sharing just one window, but I often need to share the entire desktop so multiple windows are visible.

Is there any way to prevent this effect, or to get chat messages without returning to the hangout window?