Detects Duplicate Bookmarks when bookmarks are added and specify where is the previous URL. You can also search and delete duplicates URL already in your Bookmarks.

If you have a lot of bookmarks this extension is for you !

If you think it is difficult to find a bookmark within all of them then you need this extension. BookmarkDD add possibility to search string within bookmark’s location and bookmark’s description field.
See screenshots for list of options:
http://bookmarkdd.mozdev.org/screenshots.html

You can customize this extension with its configuration panel.
Bookmark Duplicate Detector (...)

CustomizeGoogle is a Firefox extension that enhance Google search results by adding extra information (like links to Yahoo, Ask.com, MSN etc) and removing unwanted information (like ads and spam).

All features are optional and easily configured.
CustomizeGoogle (...)