The web dev toolbar for Firefox is quite an impressive tool.
What I am completely clueless about is how does this tool get the css stylesheet file of a site? This is hosted on a host which is secure etc. I am completely stumped.
I must be thinking about this in all the wrong way.
Thanks
In every HTML file, there's a link to the CSS stylesheet, or else the browser wouldn't know where to find it, thus losing the ability to render the page correctly.
It's in the form of <link rel="stylesheet" type="text/css" href="theme.css">,
The client (in this case Firefox) has to download the CSS file in order to render the page correctly. The plugin (in this case Firebug) simply requests the proper URL and the browser it gets it--most likely from the cache. There is no real mystery here.
I'd like to add that regardless of whether the host is 'secure' or not, it still is presenting the file to the client.
Unless, of course, you're looking at a XML file. Then you need to consult the XSL which'll tell you where the stylesheet is.