Place your bets: a) logic bug b) memory bug (buffer overrun/use after free/etc) c) other
1) SSL
2) HTTP/3
3) Other (DICT, FILE, FTP, FTPS, GOPHER, GOPHERS, HTTP, HTTPS, IMAP, IMAPS, LDAP, LDAPS, MQTT, POP3, POP3S, RTMP, RTMPS, RTSP, SCP, SFTP, SMB, SMBS, SMTP, SMTPS, TELNET and TFTP)
Matches the "few years back"
Luckily HTTP/3 is so complex I doubt anyone could find the issue even if they looked :-)