Comment 4 for bug 1535805

I think the easiest way to get this in GAL right now is to leave selection as it is (select everything with drag-selection). Then have a hotkey/menu item to pop the existing dialog with the checkboxes, and the reuslt of that can be used to cull the selection.

Thats get the feature in GAL before stable, and provides a hook point for improving in future (eg panel, better dialog, etc).