On Mac OS 10.5.8 with Firefox 3, when I click the Select Tags... button below, it brings up a whole page of checkboxes for previously used tags, but there is no button to click to confirm the selection, and no scroll bar to go to the botom of the page.  Only a red cross to close the window with no selection having been made.  I made a screenshot of how it looks, but there is no way to attach to this posting.