Examine source code of ProTab

{
  "manifest_version": 3,
  "name": "ProTab",
  "version": "5.0",
  "description": "Minimalist Productivity Tab",
  "icons": {
    "48": "icons/icon48.png",
    "96": "icons/icon96.png",
    "128": "icons/icon128.png"
  },
  "chrome_url_overrides": {
    "newtab": "index.html"
  },
  "permissions": [
    "storage",
    "notifications",
    "alarms"
  ],
  "host_permissions": [
    "https://meowfacts.herokuapp.com/*"
  ],
  "web_accessible_resources": [
    {
      "resources": [
        "icons/icon.png"
      ],
      "matches": [
        "<all_urls>"
      ]
    }
  ],
  "content_security_policy": {
    "extension_pages": "script-src 'self'; object-src 'self'"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "protab@thebotsite.com"
    }
  }
}