While scaling the desktop background with the window previews represents
workspaces quite intuitively, the approach is not without problems.
As window previews in the overview behave quite differently to "real"
windows, the representation of workspaces as miniature versions of
"real" workspaces is flawed. The scaling also makes the transitions
to and from the overview much more visually expensive, without adding
much benefit.
Leaving the background in place provides more visual stability to the
transitions and emphasizes the distinctive behavior of elements in the
overview.
https://bugzilla.gnome.org/show_bug.cgi?id=634948
f24e567dc4
