Web Developer Toolbar - известный набор утилит для веб-разработчика, который в сочетании с Firebug составляет незаменимый инструментарий.
The Web Developer extension adds a menu and a toolbar to the browser with various web developer tools. It is designed for Firefox, Flock and Seamonkey, and will run on any platform that these browsers support including Windows, Mac OS X and Linux.
Version 1.1.5 March 16, 2008
Added support for Firefox 3
Fixed bugs:
'Display Element Information' and 'View Style Information' could change the page when clicking
'Display Form Details' did not disable correctly on XHTML pages
Icons did not display in the customize toolbar dialog
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