Examine source code of Github Code Outline

{
  "name": "Github Code Outline",
  "version": "2.0",
  "description": "Makes code browsing on Github easy by showing outline of code.",
  "manifest_version": 2,
  "permissions": [
    "activeTab"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "https://github.com/*"
      ],
      "css": [
        "myStyles.css"
      ],
      "js": [
        "common.js",
        "content.js"
      ],
      "all_frames": true
    }
  ],
  "browser_action": {
    "default_title": "Github Code Outline",
    "default_icon": {
      "48": "images/icon_48_5.png"
    }
  },
  "web_accessible_resources": [
    "images/*.png"
  ]
}