Problem on Mac since 2009 and FF3 Rated 2 out of 5 stars
An un-addressed bug has existed for a long time. Customize toolbar has two unlabeled stars, either one of which, if dragged to the toolbar, disappears. Who knows why there are 2 or how they were intended to function if they did? I liked the feature in Google Bookmarks Button ad-on (long gone) that allowed one to easily see if a page was bookmarked and simply click on it to toggle (bookmarked/not bookmarked). Google Toolbar also did this but it is gone after FF4. Bummer. Gmarks would get 5 stars if the developer would address this bug.