Examine source code of Furaffinity Notifier

{
  "manifest_version": 2,
  "name": "Furaffinity Notifier",
  "version": "1.0.4resigned1",
  "description": " Displays the number of notifications the user has on on his signed in furaffinity.net account.",
  "icons": {
    "16": "icons/icon-16.png",
    "32": "icons/icon-32.png",
    "64": "icons/icon-64.png"
  },
  "applications": {
    "gecko": {
      "id": "jid1-g12mGXMxmco4cA@jetpack",
      "strict_min_version": "56.0"
    }
  },
  "permissions": [
    "https://www.furaffinity.net/controls/messages/",
    "storage"
  ],
  "options_ui": {
    "page": "options/options.html"
  },
  "content_scripts": [
    {
      "matches": [
        "*://www.furaffinity.net/*",
        "*://beta.furaffinity.net/*"
      ],
      "js": [
        "content/watch.js"
      ]
    }
  ],
  "browser_action": {
    "browser_style": false,
    "default_popup": "popup/summary.html",
    "default_title": "Furaffinity Notifier",
    "default_icon": {
      "16": "icons/icon-16.png",
      "32": "icons/icon-32.png",
      "64": "icons/icon-64.png"
    }
  },
  "background": {
    "scripts": [
      "background/main.js"
    ]
  }
}