Examine source code of Loudify

{
  "manifest_version": 2,
  "name": "Loudify",
  "version": "1.1",
  "description": "Increases audio from video",
  "homepage_url": "https://github.com/guileh/loudify-firefox-extension/",
  "icons": {
    "38": "icons/speaker-38.png",
    "48": "icons/speaker-48.png"
  },
  "permissions": [
    "<all_urls>",
    "tabs",
    "activeTab"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "js": [
        "main.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{8cb8bd1b-1a8e-44a9-b386-9bf15d5d56a1}"
    }
  }
}