JA4 TLS Fingerprints are comprised of three separate hashes to distinctly separate a clienthello's cipher suites and extensions from version/etc. In Service Policy client matching, clients can only be matched on the entire JA4 string.
Idea: In addition to matching clients on the whole JA4 string, adding the ability for matching on JA4_a, JA4_b, or JA4_c hashes within the calculated fingerprint would give Distributed Cloud customers more powerful options for defining Service Policy logic that spans OSI layers.