Rated 3 out of 5 stars

Great until it broke recently in FF29 because objects and pages which are not cached are showing up as cached, therefore I am unable to see Response Headers when I need to. Hope the author fixes this. Use Fiddler or Firebug in the interim (requires more clicks/steps to get to the things you want to see, though). He also has yet to fix the icon problem making it harder for some people to find/open HttpFox (use CTRL+Shift+F2 on PC to toggle)