Examine source code of Github Light Favicon

{
  "manifest_version" : 2 ,
  "name" : "Github Light Favicon",
  "version" : "1.1",
  "description" : "Changes Github's favicon to be white.",
  "icons" : {},
  "content_scripts" : [
    {
      "matches" : [
        "*://*.github.com/*" 
      ],
      "js" : [
        "github-light-favicon.js" 
      ]
    }
  ]
}