Examine source code of mCoffee

{
  "name": "mCoffee",
  "version": "1.4.6",
  "author": "Thaddaeus Kong",
  "description": "launch bookmarks based on rules.",
  "permissions": [
    "bookmarks",
    "tabs"
  ],
  "browser_action": {
    "default_icon": "icon48.png"
  },
  "background": {
    "scripts": [
      "mcoffee-MV2.js"
    ]
  },
  "manifest_version": 2,
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{3bb95b65-2578-4a48-8e35-bec5bd658ca5}"
    }
  }
}