Problem installing Zigbee2mqtt on Home Assistant

[klrock (Kerry Rock)]

Installing Zigbee2mqtt on HA supervised in VirtualBox on WIN 10 PC using instructions from GitHub - zigbee2mqtt/hassio-zigbee2mqtt: Zigbee2mqtt Home Assistant add-on
Home Assistant Add-on: Zigbee2mqtt
Installation
Add the repository URL under Supervisor → Add-on store → ⋮ → Manage add-on repositories:
GitHub - zigbee2mqtt/hassio-zigbee2mqtt: Zigbee2mqtt Home Assistant add-on
Manage add-on repositories
expected a URL @ data[‘addons_repositories’][1]. Got ’ GitHub - zigbee2mqtt/hassio-zigbee2mqtt: Zigbee2mqtt Home Assistant add-on’

I do not understand this response

[francisp (Francis)]

Make sure there is no ’ in front of the URL :

[klrock (Kerry Rock)]

Thanks for the heads up