Examine source code of Quick URL Copy

{
  "manifest_version": 2,
  "name": "Quick URL Copy",
  "version": "1.0.0",
  "description": "Copy the current tab's URL to clipboard with Cmd+Shift+U (Mac) or Ctrl+Shift+U (Windows)",
  "author": "Gilad Maoz",
  "homepage_url": "https://github.com/evilurge/quick-url-copy",
  "permissions": [
    "activeTab",
    "notifications",
    "clipboardWrite"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "commands": {
    "copy-url": {
      "suggested_key": {
        "default": "Ctrl+Shift+U",
        "mac": "Command+Shift+U"
      },
      "description": "Copy current tab URL to clipboard"
    }
  },
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{a6b9aefe-c277-42aa-8702-1575d4a7dcbb}"
    }
  }
}