Firefox Extension for web developers/designers as well as casual users "As you glide the mouse over the page, you will see a red rectangle framing each element under the cursor."
an extension that allows you to customize the menus in Firefox and Thunderbird. Broken with the new versions of FireFox now there is no alternative is seems... Firefox new GUI is so bad...
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.
visual programming environment written in JavaScript for the Mozilla Framework.Enables users to build programs graphically by connecting functional modules to fetch and direct the flow of data, play sound or video, add animation or interactivity, and disp
integrates with Firefox to put a wealth of web development tools at your fingertips while you browse. You can edit, debug, and monitor CSS, HTML, and JavaScript live in any web page.