- Web Developer Toolbar. Add a menu and a toolbar with different web development tools.
- firebug. A host of development tools at your fingertips as you browse. You can edit, debug, and monitor live CSS, HTML, and JavaScript on any web page.
- pixel perfect. It is a Firebug extension that allows web designers and developers to easily overlay a composition on top of web developed HTML code.
- IE NetRenderer. Add buttons, menus and tools from context menu entries to a screenshot of the current page with IE NetRenderer.
- colorzilla. To get a readout of the color of any point in your browser, quickly set this color and paste it into any program. It can magnify the page you are viewing and measure distances between any two points on the page.
- screen grab. Capture what can be seen in the window, the whole page, just a selection, a particular frame... basically save web pages as images either to a file or to the clipboard.
- FireFTP. FTP client for Mozilla Firefox that provides easy and intuitive access to FTP servers.
- codetech. It's like having Dreamweaver in a Firefox extension. Edit your documents together with your web pages in a simple way.
- GridFox. Draw a grid at the top of a web page. This is useful for controlling different parts of the layout.
- Font Finder. To get all CSS styles of any selected text in Firefox. Once selected, right click and select 'Font Finder', and you can see the CSS style of the selected element.
- javascript debugger. Provide a powerful JavaScript debugging environment for Mozilla-based browsers.
- Live HTTP Headers. To view the HTTP headers of a page and during navigation.
If your favorite tool is not on the list you can enter this page where you can find many accessories: https://addons.mozilla.org/es/firefox/collections/mozilla/webdeveloper/
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