The Whereisit extension is a tool that lets you quickly find where a code reference is located on GitHub. It is a part of the Official API project, developed by GitHub.

With Whereisit, you can highlight the name of a method or class and you will see where the code reference is located in the source code file.

First, you need to have the GitHub API v3 enabled for the project.

Second, you need to have your GitHub profile configured.

You can also make a full-text search of a name of a method or class and the results will show you the method or class definition, as well as the location of the code reference.