How do I access it from my webbrowser via that combination?
Just like you access any other FQDN on the planet… www.google.com is a FQDN... forum.pfsense.org is another, etc..
As to accessing it via IP, you can do that if you want.. if you don't want the error then just trust the CA you created the cert with... I have been over this multiple times, there are multiple threads about doing this.. To use an IP vs the fqdn you would have to create the SAN on the cert you want to access..
Only thing even slightly different from typical site on the internet would be if your using gui on different port than 443 you would have to put the port on the end of the fqdn via :port
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