I saw similar problem few times already and the main reason is the layout
The Collection list Wrapper has no width, then the Collection list set to
width: 100% and
When filtering happens and items getting “removed” from the container (Collection list) it shrinks automatically because 100% of nothing (remember, no width set on its parent ) is … nothing .
So if you will make Collection List wrapper to
width: 100% it will keep all containers in place and animations will not look so weird:
Hope it clears your doubts