Using a DataCollection with external data in a combo leads to empty space on the bottom of the suggest list when scrolling on a touch device (tested on google pixel2)
Unfortunately, we could not spot the issue. It can happen with dynamic list, still with a standard list everything goes smoothly.
GIF showing the problem https://gfycat.com/FickleUnfinishedCutworm
I colored the scrollbar and there are actually two scrollbars.
AFAIK the colored one shouldn't be there on a mobile device
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