Examine source code of Url Chat

{
  "short_name": "UrlChat",
  "name": "Url Chat",
  "description": "Chat with people on the same webpage as you!",
  "icons": {
    "16": "favicon.ico",
    "32": "favicon.ico",
    "48": "favicon.ico",
    "96": "favicon.ico",
    "128": "favicon.ico"
  },
  "version": "1.0.7",
  "manifest_version": 2,
  "browser_action": {
    "default_icon": {
      "16": "favicon.ico",
      "32": "favicon.ico",
      "48": "favicon.ico",
      "96": "favicon.ico",
      "128": "favicon.ico"
    },
    "default_popup": "index.html",
    "default_title": "Open the popup"
  },
  "content_security_policy": "script-src 'self'; object-src 'self'; script-src-elem 'self';",
  "permissions": [
    "tabs",
    "storage"
  ],
  "background": {
    "page": "background-page.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "urlchat@urlchat.live",
      "strict_min_version": "42.0"
    }
  }
}