DuckDNS to Remote UI - now no HTML5 notifications

To get my HA/Alexa integration working and to simplify my setup I have switched from the old DuckDNS/port forwarding method for accessing HA remotely to the new Remote UI provided by Nabu Casa.

As such I have removed base_url, ssh_certificates and ssl_key from my http config since they were only present for the DuckDNS setup. My HA URL has gone from https://my-hass.duckdns.org/ back to the default http://hassio.local:8123/.

My problem is that now I no longer have SSL when accessing HA locally, so HTML5 push notifications don’t work.

What is the recommended approach for HTML5 push notifications when you have no DuckDNS/SSL configuration set up? Should I have the ssl_ config values still set for this, even though I believe the certificates were created via the DuckDNS plugin using Let’s Encrypt?

Perhaps the only way to get HTML5 notifications is to always access HA via the external URL provided by the Remote UI, even if I’m at home?

Many thanks for any tips!