Extension's For People In Web Developing

As some of these Add-on's/Extension's won't work with Firefox 2.0 you will have to go and grab Nightly tester tools as this extension will allow you to run most extensions and themes that where made for firefox 1.5 in Firefox 2.0 by using the make all compatible option.

Web Developer Extension
adds a toolbar to the browser containing various web developer tools. It outlines page elements, displays the size of images, gives CSS and form information, disables certain elements on a page, and much more.

Accessibility Extensions
helps in the testing of a page's structural markup to meet the needs of people with disabilities. Fangs gives a textual representation of a page, similar to the way it is read by a screen reader. For more accessibility testing try the Accessibar Firefox extension or the Web Developer Extension.

Colorzilla
is an eyedropper tool. Hovering over an element shows color info, DOM path info, and the X,Y offset from the previous click.

CSSViewer
inspects elements on a page to give a complete rundown of the CSS declaration for a chosen element.

Aardvark
is a CSS debugger with keyboard modifiers. It displays items on the page such as the element name and id or class name of a selected element.

Firebug
helps in debugging AJAX, DHTML, and JavaScript web applications. It will display errors that occur during the rendering of a page, will place the pointer on the appropriate line, and allows for the inspection of different values of the DOM.

LinkChecker
checks every link on a web page to find bad links. The simple color coding scheme makes it easy to quickly spot a bad link on a page.

MeasureIt
draws a ruler across a web page to display the width, height, or alignment of any page element.

Extended Statusbar
adds information to the status bar displaying the average download speed, bytes downloaded, load time, number of loaded images and percentage of the page loaded. It is similar to Opera's status bar.

MetaTags Sidebar
displays information from the source code, such as the code lying between the tags like description, keywords, and links.

Live HTTP Headers
displays information about the HTTP headers on a page in real time.

UrlParams
is a sidebar extension that displays the form parameters Firefox has sent to the server on the last request. It will also let you change or add parameters and re-submit the request.

User Agent Switcher
allows Firefox to identify itself as a different web browser, such as IE or Opera, to a web server.

HTML Validator
adds HTML validation inside Firefox's source viewer.

IE View
allows the current page or a selected link to be opened in the Internet Explorer browser. OperaView provides the same functionality for the Opera web browser. In addition, FirefoxView allows you to open Firefox to the current page or selected link from within Internet Explorer.

Codetch
is a code editor for various markup languages. It emulates many of the features seen in Dreamweaver into a editor inside of Firefox.

Fireftp
is a FTP client which allows for easy access to a FTP server.

MozImage
is a simple image viewer and browser.

Pearl Crescent Page Saver
saves an image of a web page to a file in PNG format. The Page Saver extension uses the new canvas feature that was introduced in Firefox 1.5.

Screen Grab
takes a screenshot of a web page in several different ways. Most importantly, it allows you to capture the entire web document that you are viewing.

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