In Firefox, the server-related information is at the beginning of the URL bar. There's the favicon, and possibly the HTTPS server name. So Server Spy's UI will be there too. By default, Server Spy displays an orange badge conveying basic server identification (A for Apache, I for IIS, G for Google's software, etc.). When the user clicks on the field, the usual “server identity” dialog pops up, with an additional line containing all of the “Server” HTTP header. The orange badge (aka “icon”) may be disabled in the extension's preference dialog, while retaining the information in the popup.

20101107_ServerSpy.png

You may test the new version (at usual, at your own risks, without any kind of warranty): Server Spy 0.2.0 beta 1.

Note: it's compatible with Firefox 3.6 too (supported versions are currently 3.6 through 4.0b8pre).

Any feedback will be appreciated!