21 Add-ons in this Collection
Firebug by Joe Hewitt, Jan Odvarko, others
Greasemonkey by Anthony Lieuallen, Aaron Boodman, others
DownThemAll! by Nils Maier, Federico Parodi, others
The first and only download manager/accelerator built inside Firefox!
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...
Use the Evernote Web Clipper to save things you see on the web into your Evernote account.
Session Manager saves and restores the state of all or some windows - either when you want it or automatically at startup and after crashes. It can also automatically save the state of open windows individually.
Update news: BetterPrivacy for FF 42 has been fixed and will be uploaded to AMO shortly. Thanks for your patience!
YSlow analyzes web pages and suggests ways to improve their performance based on a set of rules for high performance web pages.
http://yslow.org is the official open source website.
HTML Validator is a Mozilla extension that adds HTML validation inside Firefox and Mozilla. The number of errors of a HTML page is seen on the form of an icon
For Online HTML 5 validation, you need 0.962
Set Default FullZoom Level,
Toolbar buttons for Page zoom and Text zoom.
Open Bookmarks/History/Homepage/URL/Search in new tabs, and more utilities for tabbed browsing, including Protect/Lock/Faviconize/Unload Tab, Reload Every, Select and manipulate multiple tabs simultaneously, Tab Stacking/Coloring, etc.
AddThis for Firefox is the best add-on to make sharing and bookmarking simple. Have all your favorite web 2.0 social networking, bookmarking, blogging, and e-mail services at your fingertips. Share any page, anytime, with anyone.
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