Examine source code of RSSTube

{
  "manifest_version": 2,
  "name": "__MSG_extensionName__",
  "description": "__MSG_extensionDescription__",
  "version": "2.1resigned1",
  "homepage_url": "https://github.com/Korbak/RSSTube",
  "icons": {
    "48": "icons/rsstube-48.png"
  },
  "permissions": [
    "activeTab"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://*.youtube.com/*"
      ],
      "js": [
        "jquery-3.2.1.min.js",
        "jquery.magnific-popup.js",
        "rsstube.js"
      ],
      "css": [
        "magnific-popup.css",
        "main.scss"
      ],
      "run_at": "document_idle"
    }
  ],
  "default_locale": "en",
  "browser_specific_settings": {
    "gecko": {
      "id": "{50b97708-af62-4146-a7ee-c88ad5837bd4}"
    }
  }
}