In IE11, setting selectedIndex of a SELECT with display:none will corrupt its scroll position.
- Click "option e" in the list.
- Use the list's scrollbar so "option e" is scrolled out of view.
- Click "display='none'".
- Click "selectedIndex=selectedIndex".
- Click "display=''".
- Move the mouse over the list, and note that the highlighted option is out of sync with the mouse cursor position.
- Click the down arrow on the scroll bar.
- Note that the list jumped to the "correct" position instead of just scrolling one line, and now everything is normal again.