A collection of extensions which I think is a must for Firefox.
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).
United States English Spellchecker for Firefox, Thunderbird and SeaMonkey by Kevin Atkinson and Geoff Kuenning.
To enable, right-click in a multi-line text box, select "Languages", then "English (United States)".
Use PDF Download to do whatever you like with PDF files on the Web. Regain control and eliminate browser problems, view PDFs directly in Firefox as HTML, and use the all-new Web-to-PDF toolbar to save and share Web pages as high-quality PDF files.
View and manage downloads from a tidy statusbar - without the download window getting in the way of your web browsing.
Thanks Tekzilla for your awesome review! Click here to see their video: http://youtu.be/BUDqWrJ-Vao
URL Fixer fixes common typos in URLs entered in the address bar. It will fix errors like "google.con" or "youtube,com". You have the option of being asked to confirm corrections before they are applied.
View publicly-accessible PDF, DOCX, PPTX, XLSX, among other files online with Google Docs by only 2 clicks. Click as usual for your default viewer. Support bookmarked URLs. Security and your explicit viewing intention are always honored.
Automatically find user scripts on Userscripts.org (requires Greasemonkey or Scriptish)
This extension allows to check the MD2, MD5, SHA1, SHA256, SHA384 or SHA512 sum of a downloaded file.
This extension notifies you when new messages arrive in your Yahoo mailbox.
NOTE: If you are having issues with the add-on reporting connection errors, try updating to version 18.104.22.168.
Add useful extra features to Gmail, like hierarchical labels, an unread message icon on your browser tab, file attachment icons, and more.
Displays Server Type, Headers, IP Address, Location Flag, and links to Whois Reports. Shows links to check server status and cache when page fails to load.
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