Open in Sourcegraph per Usator de Firefox 13930656

When you are on a github project, click on the addon button and it will open a new tab with the same project on https://sourcegraph.com/.

The main difference between this and the official addon is that about 50% of the times that I want to use the official it says that I must configure it first. After a refresh it works, but I don't want to do this everytime. My addon is much more simple and it works for me on chrome and now on firefox.