Examine source code of Mail.com Deref

{
  "manifest_version": 3,
  "name": "Mail.com Deref",
  "version": "1.1.1",
  "description": "Makes links in Mail.com emails point directly to their destination, rather than being routed through deref-mail.com.",
  "permissions": [
    "activeTab"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://*.mail.com/*",
        "https://mailcom.mailbody-ui.de/**"
      ],
      "all_frames": true,
      "js": [
        "fixlinx.js"
      ]
    }
  ],
  "icons": {
    "32": "icon.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "@mail-com-deref",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}