Functionality Pack

by Jack Thomas

9 Add-ons in this Collection

Firebug by Joe Hewitt, Jan Odvarko, others

Rated 5 out of 5 stars 1,791 reviews

2,434,982 users

Firebug integrates with Firefox to put a wealth of development tools at your fingertips while you browse. You can edit, debug, and monitor CSS, HTML, and JavaScript live in any web page...

DownThemAll! by Nils Maier, Federico Parodi, others

Rated 5 out of 5 stars 1,610 reviews

1,410,754 users

The first and only download manager/accelerator built inside Firefox!

Web Developer by chrispederick

Rated 5 out of 5 stars 217 reviews

600,881 users

The Web Developer extension adds various web developer tools to the browser.

Tamper Data by Adam Judson

Rated 4 out of 5 stars 132 reviews

120,955 users

Use tamperdata to view and modify HTTP/HTTPS headers and post parameters...

Xmarks Sync by Xmarks Inc.

Rated 4 out of 5 stars 2,516 reviews

325,618 users

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!

PDF Download by Nitro PDF Software

Rated 2 out of 5 stars 682 reviews

129,984 users

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.

British English Dictionary by Mark Tyndall

Rated 3 out of 5 stars 422 reviews

250,582 users

British English Dictionary R1.19 for Firefox, Thunderbird and SeaMonkey by David Bartlett.

To enable, right-click in a multi-line text box, select "Languages", then "English / United Kingdom".

ImgLikeOpera by Danil Ivanov

Rated 4 out of 5 stars 354 reviews

116,466 users

ImgLikeOpera allows load only the images that you want in Firefox browser. This extension is very useful for non broadband users...

Better Gmail 2 by Gina Trapani

Rated 4 out of 5 stars 516 reviews

16,701 users

Add useful extra features to Gmail, like hierarchical labels, an unread message icon on your browser tab, file attachment icons, and more.

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