Addon Developers Kit
27 Add-ons in this Collection
Firebug by Joe Hewitt, Jan Odvarko, others
The Web Developer extension adds various web developer tools to the browser.
Use tamperdata to view and modify HTTP/HTTPS headers and post parameters...
View HTTP headers of a page and while browsing.
Adds an about:addons-memory page that details add-on memory usage
DOM Inspector is a tool that can be used to inspect and edit the live DOM of any web document or XUL application. The DOM can be navigated using a two-paned window displaying a variety of different views on the document and all nodes within.
Help make Firefox better. The Add-on Compatibility Reporter enables you to report if the Firefox add-ons that you're using are working properly.
It adds a tab to the Page Info dialog box, which shows the cookies belonging to the current page.
Extension Auto-Installer is a helper for Firefox/SeaMonkey/Thunderbird extension developers: it allows automatically adding or updating browser extensions, e.g. via command line tools. This makes testing your changes easier.
Adds a clear cache toolbar button. After installing the extension, find the clear cache button in the toolbar customization...
Easy cache status & management from status...
Install Browser Extensions straight from GitHub Repositories