Examine source code of Content Unlocker

{
  "manifest_version": 3,
  "name": "Content Unlocker",
  "version": "1.0.0",
  "description": "Automatically removes login/signup overlays and restores page readability",
  "permissions": [
    "activeTab",
    "scripting"
  ],
  "host_permissions": [
    "<all_urls>"
  ],
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_start",
      "all_frames": false
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "content-unlocker@example.com",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}