Examine source code of Facebook On One Click

{
  "description": "This web extension open Facebook on just one click",
  "manifest_version": 2,
  "name": "Amazon",
  "version": "1.0",
  "author": "Parul Gupta",
  "homepage_url": "https://github.com/PearlGu",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": {
      "48": "icon.png",
      "96": "icon2.png"
    }
  },
  "icons": {
    "48": "icon.png"
  }
}