Examine source code of frame capture

{
  "manifest_version": 2,
  "name": "Frame",
  "version": "1.0.0",
  "browser_specific_settings": {
    "gecko": {
      "id": "claertobaila@outlook.com",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "description": "No data is collected. Screenshots are processed locally and never transmitted."
      }
    }
  },
  "description": "Capture full-page screenshots or selected regions with an intuitive overlay tool. Capture, copy, download, or annotate directly from the popup.",
  "permissions": [
    "activeTab",
    "storage",
    "downloads",
    "clipboardWrite",
    "<all_urls>"
  ],
  "browser_action": {
    "default_popup": "board/ui.html",
    "default_title": "Frame — Screenshot Tool",
    "default_icon": {
      "16": "icons/frame-bit-16.png",
      "48": "icons/frame-bit-48.png",
      "96": "icons/frame-bit-96.png"
    }
  },
  "background": {
    "scripts": [
      "engine/background.js"
    ],
    "persistent": false
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "overlay/selector.js"
      ],
      "css": [
        "overlay/selector.css"
      ],
      "run_at": "document_idle"
    }
  ]
}