My Favorite Add-ons

by Francisco Javier

11 Add-ons in this Collection

Firebug by Joe Hewitt, Jan Odvarko, others

Rated 4 out of 5 stars 2,565 reviews

932,744 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 4 out of 5 stars 2,603 reviews

737,723 users

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

Web Developer by chrispederick

Rated 4 out of 5 stars 448 reviews

282,679 users

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

ColorZilla by Alex Sirota

Rated 4 out of 5 stars 417 reviews

184,859 users

Advanced Eyedropper, Color Picker, Gradient Generator and other colorful goodies...

Xmarks Sync by Xmarks Inc.

Rated 3 out of 5 stars 3,164 reviews

100,998 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!

X-notifier (for Gmail,Hotmail,Yahoo,AOL ...) by Byungwook Kang

Rated 4 out of 5 stars 1,782 reviews

42,131 users

Notifier for gmail, yahoo, hotmail, aol and more webmails.
X-notifier(aka WebMail Notifier) checks your webmail accounts and notifies the number of unread emails...
Supports : gmail, yahoo, hotmail, POP3/IMAP, facebook, twitter and more

PDF Download by Nitro PDF Software

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Experimental

Rated 2 out of 5 stars 664 reviews

21,092 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.

Html Validator by Marc Gueury

Rated 4 out of 5 stars 211 reviews

33,767 users

HTML Validator is a Mozilla extension that adds HTML validation inside Firefox, Mozilla. The number of errors of a HTML page is seen on the form of an icon

For Firefox 56, use 0.974 (see all versions below).
For Firefox 57, see Web Extensions.

Pencil by Dương Thành An, Brainiac

Rated 4 out of 5 stars 92 reviews

300 users

Pencil is a Firefox add-on to do GUI prototyping and simple sketching

FireQuery by BinaryAge, Jan Odvarko

Rated 4 out of 5 stars 54 reviews

7,114 users

Firebug plugin for jQuery development

iReader by MhdHejazi

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Experimental

Rated 4 out of 5 stars 102 reviews

1,459 users

View news stories and other articles in a very easy to read, clutter-free, scrollable display.

What are Collections?

Collections are groups of related add-ons that anyone can create and share.

Explore Collections