Examine source code of Gitark

{
  "name" : "Gitark",
  "version" : "0.1.0",
  "short_name" : "Gitark",
  "author": "imfunny and community",
  "description" : "the most popular dark theme extension for github",
  "manifest_version" : 2 ,
  "icons" : {
    "16" : "./assets/icons/icon3.png",
    "48" : "./assets/icons/icon2.png",
    "128" : "./assets/icons/icon1.png"
  },
  "content_scripts" : [
    {
      "css" : [
        "src/style.css" 
      ],
      "matches" : [
        "https://github.com/*" 
      ],
      "js" : [
        "src/content.js" 
      ],
      "run_at" : "document_start" 
    }
  ]
}