Github Profile Extender gives you a quick overview of a Github user or the author of a repository, or a gist.

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This extension works on all pages that are owned by any Github user, gist.github.com/[username]/* and github.com/[username]/* etc.

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You get to see info that is shown on Github user profile page and more! Without leaving the page you are browsing, so no need to go to check info about the author from the actual profile page.

Here is an example how it looks like on your browser: