Examine source code of Full Screener

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "manifest_version": 2,
  "name": "Fullscreen Anything",
  "version": "2",
  "author": "Arno van den Brink",
  "description": "Maximizes images, videos, and games.",
  "offline_enabled": true,
  "permissions": [
    "http://*/*",
    "https://*/*"
  ],
  "icons": {
    "16": "img/icon16.png",
    "48": "img/icon48.png",
    "128": "img/icon128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "http://*/*",
        "https://*/*"
      ],
      "css": [
        "css/style.css"
      ],
      "js": [
        "js/content.js"
      ],
      "run_at": "document_idle",
      "all_frames": true
    }
  ],
  "background": {
    "persistent": false,
    "scripts": [
      "js/background.js"
    ]
  },
  "browser_action": {
    "default_icon": {
      "19": "img/icon19.png",
      "38": "img/icon38.png"
    },
    "default_title": "Toggle Tabcinema"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{222e847c-547e-4307-a70e-03af7812956f}"
    }
  }
}