Code review comment for lp:~robertcarr/mir/alpha-for-nested-servers

> I assuming the nesting and/or alpha blending is disabled after login? Otherwise the performance overhead would be quite high.

The unity8 shell session will not take advantage of this background opacity. It will always just fill the screen with its dash. I assume if the background is filled with a surface, there isn't a performance overhead?

The greeter won't use any clever blending or blurring effects for the first go, just have some 0-opacity parts of the screen. Later on, we want to add some blurring, but that would of course go away after you log in.