WTreeView items duplication and corruption
If I open WTreeView demo on WT site and change the size of my Chrome browser so that there are scrolls on TreeView, and then start to scroll the tree with scroll arrow-buttons, eventually tree becomes corrupted (see screenshot). Items are duplicated, also there are randomly placed empty spaces between items.
I checked this on git version - same behavior.
It seems that bigger vertical scroll range leads to this error faster. So fastest way to reproduce this error is to shrink browser as shown on screenshot.