On: Special-use domain 'home.arpa.' (2018)

[_flux]

Thank you! I'll try that with my next CA, which I think is actually expired but it seems not all apps care about that :).

If "relatively modern" covers browsers and email clients, that's pretty good already.

edit: here's the reference: https://datatracker.ietf.org/doc/html/rfc5280#section-4.2.1.... and here's a practical example: https://systemoverlord.com/2020/06/14/private-ca-with-x-509-...