BookmarkDD - It notices when a duplicate bookmark is added. LiveClick - Enhances Live Bookmarks with links to home pages, favicons, notifications and other feed reading features. Memotoo.com for Firefox - Allows to synchronize bookmarks with memotoo.com and use the Memotoo sidebar and toolbar in Firefox. QuickFox - A multi-tab note taking add-on that uses the browser's existing bookmarks system to store notes. Shareaholic - Shares and bookmark web-pages on popular social sharing and bookmarking services. Xmarks - Offers bookmark synchronization, search enhancement and web discovery based on sites bookmarked by users. Bookmarks Toolbar Button - Makes the Bookmarks button on your toolbar toggle the Bookmarks Toolbar instead of the Bookmarks Sidebar. Categorize - Based on the insight that bookmarks are not all equally important, provides the following features: categories, groups, menu lists, tab-sets, auto-complete and helpers to classify, organize, manage and access to bookmarks. Site contains support forum, wiki, and vast documentation about ontology problems that bookmarking presents. Bookmarks LinkChecker - Detects updated, redirected and broken links in bookmarks list by adding icons within the drop-down bookmarks menu. Places Full Titles - Shows bookmarks full titles in the bookmarks menu and submenus. Firesort - A graphical utility that can alphabetically sort standard Firefox bookmark files.