It happened the same to me when a notification popped up while alt-tabbing
Il giorno 14/giu/2012 05.35, "Cassidy James" <email address hidden> ha scritto:

> That white padding is shown on the display, btw.
>
> ** Changed in: gala
>   Importance: Undecided => Critical
>
> ** Summary changed:
>
> - Gala flips out and makes everything miniature
> + Alt+Tabbing when a window opens makes everything miniature
>
> ** Description changed:
>
> - Occasionally when I do something apparently Gala doesn't like (such as
> - fullscreening Winecraft or alt+tabbing a bunch of times between tiled
> - windows), Gala will flip out and throw a tantrum in which it looks as if
> - my display has been miniaturized in the middle of my physical display,
> - with a large white border around it. Mousing around shows that
> - everything is in its proper (larger) place, but is getting drawn
> - smaller. Alt+tabbing makes windows show at the proper size, but once
> - you're out of the window switcher, everything is miniature again. The
> - only way I've found to restore things is a quick gala --replace.
> + When a window opens while I'm alt+tabbing, Gala will flip out and throw
> + a tantrum in which it looks as if my display has been miniaturized in
> + the middle of my physical display, with a large white border around it.
> + Mousing around shows that everything is in its proper (larger) place,
> + but is getting drawn smaller. Alt+tabbing makes windows show at the
> + proper size, but once you're out of the window switcher, everything is
> + miniature again. The only way I've found to restore things is a quick
> + gala --replace.
>
>  I realize this is complicated and confusing, but at the same time it's
>  pretty severe; no ordinary user would be able to recover and it makes
>  things feel extremely broken. I'm uploading a video to demonstrate the
>  bug and will try to do more research/experimenting to track down the
>  cause.
>
>  Notable info:
>  - Resolution: 1366 x 768
>  - Number of displays: 1
>  - OS: elementary OS Luna daily build 32-bit (Ubuntu 12.04)
>
> ** Changed in: gala
>    Milestone: None => luna-beta1
>
> --
> You received this bug notification because you are a member of Gala
> developers, which is subscribed to Gala.
> https://bugs.launchpad.net/bugs/1011699
>
> Title:
>  Alt+Tabbing when a window opens makes everything miniature
>
> Status in Gala Window Manager:
>  New
>
> Bug description:
>  When a window opens while I'm alt+tabbing, Gala will flip out and
>  throw a tantrum in which it looks as if my display has been
>  miniaturized in the middle of my physical display, with a large white
>  border around it. Mousing around shows that everything is in its
>  proper (larger) place, but is getting drawn smaller. Alt+tabbing makes
>  windows show at the proper size, but once you're out of the window
>  switcher, everything is miniature again. The only way I've found to
>  restore things is a quick gala --replace.
>
>  I realize this is complicated and confusing, but at the same time it's
>  pretty severe; no ordinary user would be able to recover and it makes
>  things feel extremely broken. I'm uploading a video to demonstrate the
>  bug and will try to do more research/experimenting to track down the
>  cause.
>
>  Notable info:
>  - Resolution: 1366 x 768
>  - Number of displays: 1
>  - OS: elementary OS Luna daily build 32-bit (Ubuntu 12.04)
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/gala/+bug/1011699/+subscriptions
>