Examine source code of Social Fade

{
  "manifest_version": 2,
  "name": "Social Fade",
  "version": "0.1.3",
  "author": "Wesley Junio",
  "description": "Limits the use of registered sites for a certain period of time.",
  "permissions": [
    "storage",
    "tabs"
  ],
  "icons": {
    "48": "icons/sf48.png",
    "96": "icons/sf96.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "script/socialfade.js"
      ]
    }
  ]
}