Resizing item and spell views with a mouse leads to breakage when controller tooltips are on

If the controller UI is used and controller tooltips are enabled, the widgets that have item or spell views in them get corrupted when they're resized due to the item view controller focus update warping the mouse to re-highlight the tooltip of the focused item and confusing MyGUI.

Sometimes it leads to crashes like this one. openmw-crash.log

This probably affects spell views as well.

No clue how to fix this "properly".