Examine source code of FullscreenElement

{
  "manifest_version": 2,
  "name": "__MSG_extensionName__",
  "description": "__MSG_extensionDescription__",
  "version": "1.1",
  "default_locale": "en",
  "web_accessible_resources": [
    "icons/*.png"
  ],
  "icons": {
    "48": "icons/48x48.png",
    "96": "icons/96x96.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "js/content_script.js"
      ],
      "match_about_blank": false,
      "all_frames": false,
      "run_at": "document_idle"
    }
  ]
}