Rated 5 out of 5 stars

per blseal el ago. 22, 2009 ·

Spyder, Lucian, sounds like you're looking for Server Spy (https://addons.mozilla.org/en-US/firefox/addon/2036). Nice little addon, displays the web server type in the status bar, and double-clicking on it displays additional details (like what extensions have been loaded on it).

As for LiveHTTPHeaders, it's the best addon of its type!

This review is for a previous version of the add-on (0.15).