Firefox extensions for developers

To develop a Web application, to design a dynamic Web page with precision, find sources of errors and have a view on the state of exchanges between the browser and the server, Firefox may be transformed into a software programming and a testing tool thanks to these extensions.

Editing

View Formatted Source
Displaying the HTML source code indented and colorized.

Font Finder
Show CSS styles for selected content items and lets you know how it was achieved.

ColorZilla
Takes a color on the page to allow for use elsewhere. Proposes a palette.

MeasureIt
Displaying a rule to adjust sizes.

Tuning and debugging code

Firebug
Debugger for JavaScript and Ajax.Shows the contents of the exchanges between the browser and the server.

Page Speed
Performance tool for your pages. The installation adds the Page Speed tab in the Firebug control panel (which is required) from which you can scan a page and get optimization advices.

The Web Developer
A menu added to Firefox includes several tools.

Modify Headers
Using HTTP headers. Lets you create ones.

Web page optimisation

You can view a tag cloud on the results pages of Google with the Cloudlet extension. This helps the user to refine his request, but it's also very useful to the webmaster by showing the semantics associated with a keyword.

HTML Validator
Includes a compatibily checking feature for the HTML code and compliance with the standard.

SEO Quake
Adding a toolbar with numerous indications about the importance of a site or a page. Works with Firefox and Internet Explorer.

Link Analysis
Completed Google Tools for Webmasters. When you click on the list of backlinks to a given page, displays of PR backlinks and those which have disappeared (mainly from RSS files).

iWebTool
Provides access to some thirty tools especially on the links and the position of the site. Availability of a domain name. Extracting HTML contents.

KGey
Extract main keywords in a web page.

Compatibility with browsers and mobiles

FxDT
From Firefox allows you to test whether an application is working on other browsers, without leaving the current environment.

Quick Locale Switcher
Change the language of the browser.

XHTML-MP
Displays the sites's contents in mime type of mobiles: 'application/vnd.wap.xhtml+xml'.