Examine source code of Google Forms Toolbox

{
  "name": "__MSG_appName__",
  "short_name": "__MSG_appShortName__",
  "description": "__MSG_appDescription__",
  "version": "1.0.0",
  "default_locale": "en",
  "icons": {
    "16": "assets/img/16x16.png",
    "32": "assets/img/32x32.png",
    "48": "assets/img/48x48.png",
    "128": "assets/img/128x128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://docs.google.com/forms/*"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "content.css"
      ],
      "run_at": "document_end"
    }
  ],
  "manifest_version": 2,
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": "assets/img/128x128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{9ebec9a7-4758-4033-9ebd-93803f8ed45f}"
    }
  }
}