Examine source code of Restore Link Card

{
  "manifest_version": 2,
  "name": "Restore Link Card",
  "short_name": "RestoreLinkCard",
  "version": "3.0.3",
  "description": "A browser extension to restore OGP link cards on Twitter (X).",
  "icons": {
    "128": "image/icon.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://twitter.com/*",
        "https://mobile.twitter.com/*",
        "https://pro.twitter.com/*",
        "https://x.com/*",
        "https://mobile.x.com/*",
        "https://pro.x.com/*"
      ],
      "js": [
        "js/loader.js"
      ],
      "css": [
        "css/style.css"
      ]
    }
  ],
  "web_accessible_resources": [
    "js/main.js"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{be3279c5-c7f8-498a-a815-054dcdb7e766}"
    }
  }
}