On touch devices a scrollbar will be rendered if a item inside the table is selected. It hasn't any use and won't disappear.
As a rule, webix.CustomScroll shouldn't be used on touch devices, as it will conflict with the touch scrolls (Webix initializes a touch scroll on any mobile/touch device automatically). webix.CustomScroll's purpose is to replace the native browser scroll to make it look and behave more like the touch scroll, and is not meant to be initialized on touch devices.
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