Pretty awesome addon. It's so much more convenient to just view the source files in the browser than to download the .xpi, unzip it, and go in and out of folders to find things. This addon saves me a lot of time and annoyance.
I saw on GitHub that an option is being considered to make clicking the icon take you directly to the source viewer, which would make this addon even more awesome. :D
EDIT: I just updated and it works great, thank you!