Certificate error about proxmox_hassos_install

[whiskerz007]

This is because Proxmox is using, by default, a self-signed certificate for the web server. This is so that the traffic between your computer and Proxmox is encrypted. The certificate warning is generated by the browser. You can add the certificate to your computer's trusted certificate list, which should eliminate this warning from occurring. You can also change the certificate Proxmox uses to a signed one from a trusted Certificate Authority, but this is unlikely something a home user would do, due to the complexities.