iconGrid: Only animate visible icons
Mutter recently added an optimization to only allocate visible children [1]. That broke ClutterClones, but it was subsequently fixed [2].
However, that exposed a third problem, this time with FrequentView: visible but transparent icons, that are not allocated by the icon grid, were cloned and animated during the spring animation.
Only animate visible icons with opacity greater than 0.
[1] mutter@0eab73dc [2] mutter@08a3cbfc
Edited by Georges Basile Stavracas Neto