Examine source code of CoolTab

{
  "manifest_version": 3,
  "name": "Cool Tab",
  "version": "1.13.4",
  "description": "Just a new tab for your browser, but cooler",
  "chrome_url_overrides": {
    "newtab": "index.html"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "host_permissions": [
    "https://query1.finance.yahoo.com/*",
    "https://query2.finance.yahoo.com/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "cooltab@github.io",
      "strict_min_version": "60.0"
    }
  }
}