Florian Müllner authored Jun 18, 2019 and Marco Trevisan committed Jun 18, 2019

Since commit 520cea93, the opacity of icon grid children is used
both to skip children outside the current viewport and to hide the
real icons while animating icon clones.

As a result, a grid animation during an animation now ends up showing the
icons that are being animated. Avoid that glitch by leaving children's
opacity alone when there's an ongoing animation.

!582