Man pages matching name ext_session_acl in section 8:

ext_session_acl.8.en	debian 10 / squid
ext_session_acl.8.en	debian 11 / squid
ext_session_acl.8.en	debian 11 / squid-openssl
ext_session_acl.8.en	debian 12 / squid
ext_session_acl.8.en	debian 12 / squid-openssl