Examine source code of demoexttmt

{
  "manifest_version": 2,
  "name": "demoexttmt",
  "version": "1.2",
  "description": "Adds a red border to all webpages matching mozilla.org website",
  "icons": {
    "48": "icons/border-48.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.mozilla.org/*"
      ],
      "js": [
        "borderify.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "hello@g43.in",
      "strict_min_version": "65.0"
    }
  }
}