Is there a development tool plugin for Safari much like how there exists the Firebug plugin for Firefox?
I work a lot with CSS panel and it's too slow in Safari Web Inspector. Apple knows about this problem and promise to fix this bug with freezes, except this thing web tools is much more powerful and convenient than firebug in mozilla, so waiting for fix.
If you want firebug for Safari, you just have to go to the apple extensions and search for Firebug
Firebug
Firebug is great, but Safari provides its own built-in development tools.
If you haven't already tried Safari's development kit, go to Safari-->Preferences-->Advanced, and check the box next to "Show Develop menu in menu bar".
Once you have the Develop menu enabled, you can use the Web Inspector to get a lot of the same functionality that Firebug provides.
Why do you want to use Firebug if Safari already comes with great Developer tools? :)
As Matt said, you can enable them from the preferences menu.
Here you will find an overview, summarized, of the Safari's Web inspector, and how to use it:
http://getfirebug.com/lite/Safari.html
http://getfirebug.com/firebuglite
Firebug lite plugin in Safari extensions didn't work (it's made by slicefactory, I don't think it's offical). btw, #2 works for me!