Created attachment 219632 [details]
comboboxes are drawn incorrectly

When a combobox menu pops up most of the time it's half empty and I have to scroll to get the invisible menu items onto my screen.

(see attached screenshot)

I think this is because the active menu item is being selected and centered above the combobox itself.
Sometimes this is not possible depending on the screen location of the combobox and the amount of menu items.

A better solution would be to just display the menu list above or below the combobox as shown here: http://www.brad-smith.info/blog/wp-content/uploads/2010/06/GroupedComboBox.jpg
(right combobox)

The combobox itself shows the selected menu item and additionally it's shown in the menu list.