Where do I turn on HTTPS for my external domain?

Hello !

I own a domain with an .at TLD on an austrian service and I wondered where I can turn on SSL for it on Editor X?

I cannot transfer the domain because the .at TLD is not supported by Editor X, but it would be essential to have that HTTPS.

When checking the A and CNAME DNS records as suggested here: https://support.wix.com/en/article/checking-your-domains-dns-records-using-whatsmydnsnet#checking-your-domains-pointing-connection-1

I can see the update on most locations, but I still receive a " ERR_SSL_PROTOCOL_ERROR" in Chrome.

However the page is fully built in Editor X and the domain is connected via pointing (A & CNAME records).

When I google “Editor X activate SSL” I get this result here https://support.wix.com/en/article/about-ssl-and-https but that does not help me unfortunately.

I would truly appreciate help on this topic!

Best regards and thanks!