Must 2 Be Firefox Add-ons by Lyderis.com without any Whistles & Bells
Blocks annoying video ads on YouTube, Facebook ads, banners and much more.
Adblock Plus blocks all annoying ads, and supports websites by not blocking unobtrusive ads by default (configurable).
The first and only download manager/accelerator built inside Firefox!
Download all the links, movies and audio clips of a page at the maximum speed with a single click, using the most popular, lightweight and reliable external download managers.
This add-on is a downloader that lets you easily download videos from sites like Youtube, Facebook, Metacafe, Dailymotion, Break, VKontakte and music for example from SoundCloud, Grooveshark and from many other sites...
Never be annoyed by a Flash animation again! Blocks Flash so it won't get in your way, but if you want to see it, just click on...
This extension allows you to export your saved passwords and disabled login hosts using XML or CSV files that can be imported later.
UnMHT allows you to view MHT (MHTML) web archive format files, and save complete web pages, including text and graphics, into a single MHT file in Firefox/SeaMonkey.
This extension prevents Google, Yahoo and Yandex search pages from modifying search result links when you click them. This is useful when copying links but it also helps privacy by preventing the search engines from recording your clicks.
Visual bookmarks for Firefox. (Works with all latest versions of Firefox)
Allows editing of web page content while in Print Preview mode, prior to printing or saving as HTML or PDF. Compacts the layout and removes unwanted content such as adverts, sidebars and blank pages. Any element can be formatted, hidden or deleted.
Adds the ability to create and edit entries in the password manager.
Tweak Network will speed up the loading of web pages and increase the maximum number of simultaneous downloads from a site.