https://caddy.community/t/random-ocsp-response-errors-for-random-clients/2473?u=matt

Certificates are keyed by name in the cache, optimized for fast lookups
during TLS handshakes using SNI. A more "correct" way that is truly a
1:1 would be to cache certificates by a hash of the leaf's DER bytes,
but this involves an extra index to maintain. So instead of that, we
simply choose to prevent overlap when keying certificates by server
name. This avoids the ambiguity when updating OCSP staples, for instance.