Examine source code of PocketTube: Youtube Subscription Manager

{
  "manifest_version": 2,
  "name": "__MSG_name__",
  "short_name": "YSM",
  "description": "__MSG_description__",
  "author": "Dmitry Nabok",
  "homepage_url": "https://pockettube.io/",
  "default_locale": "en",
  "version": "18.7.9",
  "content_scripts": [
    {
      "matches": [
        "https://*.youtube.com/*"
      ],
      "js": [
        "/build/app.js",
        "/purify2.min.js"
      ],
      "css": [
        "/build/context.css"
      ],
      "run_at": "document_start"
    }
  ],
  "background": {
    "scripts": [
      "build/background.js"
    ]
  },
  "web_accessible_resources": [
    "/build/utf.js",
    "/purify2.min.js",
    "/pockettube-app/dist/*",
    "/popup/login.html",
    "icon/*",
    "patreon/*"
  ],
  "permissions": [
    "alarms",
    "storage",
    "unlimitedStorage",
    "identity",
    "contextMenus",
    "https://*.youtube.com/*",
    "webRequest"
  ],
  "host_permissions": [
    "https://*.youtube.com/*"
  ],
  "optional_permissions": [
    "bookmarks",
    "https://*.googleapis.com/*",
    "notifications"
  ],
  "browser_action": {
    "default_icon": "/icon/icon_48.png",
    "default_popup": "/pockettube-app/dist/index.html",
    "default_title": "PocketTube: Youtube Subscription Manager"
  },
  "icons": {
    "16": "/icon/icon_16.png",
    "48": "/icon/icon_48.png",
    "128": "/icon/icon_128.png"
  },
  "applications": {
    "gecko": {
      "id": "danabok16@gmail.com",
      "strict_min_version": "58.0"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "danabok16@gmail.com",
      "strict_min_version": "58.0"
    }
  }
}