Examine source code of GeniuSpot

{
  "name": "__MSG_appName__",
  "short_name": "__MSG_appShortName__",
  "description": "__MSG_appDescription__",
  "version": "0.0.1",
  "manifest_version": 2,
  "default_locale": "en",
  "icons": {
    "16": "images/icon-16.png",
    "128": "images/icon-128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://*.genius.com/*"
      ],
      "js": [
        "scripts/genius-inject.js"
      ],
      "exclude_matches": [
        "https://*.genius.com/artists/*",
        "https://*.genius.com/albums/*",
        "https://*.genius.com/search",
        "https://*.genius.com/"
      ]
    }
  ],
  "background": {
    "scripts": [
      "scripts/background.js"
    ]
  },
  "browser_action": {
    "default_icon": {
      "19": "images/icon-19.png",
      "38": "images/icon-38.png"
    },
    "default_title": "__MSG_browserActionTitle__",
    "default_popup": "pages/popup.html"
  },
  "permissions": [
    "storage"
  ]
}