Bizarre, ssllabs test says IPv4 "A+", IPv6 "T" (whatever that means, Qualys). I see the TLS error on direct connection, with Brave (Chromium), but have only IP

Bizarre, ssllabs test says IPv4 "A+", IPv6 "T" (whatever that means, Qualys). I see the TLS error on direct connection, with Brave (Chromium), but have only IPv4 connectivity.