When changing the width of the object browser or the window list (both fixed to the left side of the screen) having a vertical scrollbar, there is a point where the cursor flickers and switches rapidly between the pointer/arrow icon (normal cursor icon in the e.c. object browser) and the 'change width' icon (two vertical lines with small arrow symbols to the left and right). When you click with the mouse, it is the pointer/arrow icon that 'wins'
Not a big issue but it seems that the change width icon is activated twice when moving the cursor one pixel at a time, even in a window without scrollbar, so maybe it has something to do with this.