Examine source code of randomMDN

{
  "manifest_version": 2,
  "name": "randomMDN",
  "version": "0.1",
  "description": "Learn something new! Goes to a random MDN page at the press of a button ",
  "browser_specific_settings": {
    "gecko": {
      "id": "randomdn@colemaguire.me",
      "strict_min_version": "62.0"
    }
  },
  "background": {
    "scripts": [
      "js/main.js",
      "js/attach-events.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://developer.mozilla.org/*"
      ],
      "js": [
        "js/main.js",
        "js/add-button.js"
      ]
    }
  ],
  "permissions": [
    "*://developer.mozilla.org/*",
    "*://www.iana.org/assignments/language-subtag-registry/language-subtag-registry",
    "webRequest",
    "storage",
    "activeTab"
  ],
  "browser_action": {
    "default_icon": "icons/mdn_logo.png",
    "default_title": "Random page!"
  },
  "options_ui": {
    "page": "html/settings.html",
    "browser_style": true
  },
  "icons": {
    "48": "icons/mdn_logo_48.png",
    "96": "icons/mdn_logo_96.png"
  }
}