Working on the web all day, every day? Then you might benefit from these add-ons - at least I hope you do :)
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!
The best security you can get in a web browser!
Allow active content to run only from sites you trust, and protect yourself against XSS and Clickjacking attacks.
The Web Developer extension adds various web developer tools to the browser.
Xmarks is the #1 bookmarking and open tab add-on. Keep your bookmarks, and open tabs backed up and synchronized across computers and browsers. Mobile phones with Premium access. Utilize LastPass to sync passwords!
Protect your Passwords, Payments, and Privacy.
— Open web pages saved with Internet Explorer or other browsers (MHT)
— Save many tabs, video and audio reliably, in a single ZIP file (MAFF)
— Return to the original site you saved a page from, and more!
Evernote Clearly makes blog posts, articles and webpages clean and easy to read. Save them to Evernote to read anywhere.
TinEye is a reverse image search engine. The plugin adds a context menu item that allows you to search for an image to find out where it came from, how it is being used, if modified versions of the image exist, or to find higher resolution versions.
Make your bookmarks bar better. Roomy Bookmarks Toolbar can: hide bookmarks/folders name(dock like), multirow, autohide and many another features(more than 20).
Customize your bookmarks bar using one add-on.
Never lose anything you type into a web form again! Lazarus securely auto-saves all forms as you type, so after a crash, server timeout, or whatever, you can go back to the form, right click, "recover form", and breathe a sigh of relief.