Examine source code of Tab-Address

{
  "manifest_version": 2,
  "name": "Tab Address Clipboard",
  "version": "1.0",
  "description": "Copy the address of the currently selected tab to the clipboard.",
  "permissions": [
    "tabs",
    "clipboardWrite"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{7b770c3f-1b6d-4ccc-aa27-16921017083c}"
    }
  }
}