Examine source code of Smart Zoom Bubble

{
  "manifest_version": 2,
  "name": "Smart Zoom Bubble",
  "version": "1.0.1",
  "description": "Double-click image → movable magnifying bubble (2–6x)",
  "permissions": [
    "activeTab",
    "scripting",
    "<all_urls>"
  ],
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "bubble.js"
      ],
      "run_at": "document_end"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "smart-zoom-bubble@example.com",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "collects": false
      }
    }
  }
}