Examine source code of Minimal Tetromino Friends

{
  "content_scripts": [
    {
      "js": [
        "mtf.user.js"
      ],
      "matches": [
        "*://*.tetrisfriends.com/*"
      ],
      "run_at": "document_start"
    }
  ],
  "background": {
    "scripts": [
      "events.js"
    ],
    "persistent": true
  },
  "options_page": "options.html",
  "browser_action": {
    "default_popup": "options.html",
    "default_icon": {
      "16": "logo16.png",
      "48": "logo48.png",
      "128": "logo128.png"
    }
  },
  "description": "Reduces lag as much as possible by removing everything from the page except for the game itself.",
  "icons": {
    "16": "logo16.png",
    "48": "logo48.png",
    "128": "logo128.png"
  },
  "manifest_version": 2,
  "name": "Minimal Tetromino Friends",
  "short_name": "mtf",
  "permissions": [
    "webRequest",
    "webRequestBlocking",
    "*://*.tetrisfriends.com/*",
    "*://tetrisow-a.akamaihd.net/*",
    "storage"
  ],
  "version": "5.0.1",
  "applications": {
    "gecko": {
      "id": "{936c9dbf-25a7-433f-8223-08693060c5da}",
      "strict_min_version": "45.0"
    }
  }
}