JA3 / TLS Fingerprint always contains commas

Hey there,

We’re using the new functions in HAProxy 2.5 to generate a JA3 header.
However the JA3 headers always contains commas.

      http-request set-header X-SSL-JA3 %[ssl_fc_protocol_hello_id],%[ssl_fc_cipherlist_bin(1),be2dec(-,2)],%[ssl_fc_extlist_bin(1),be2dec(-,2)],%[ssl_fc_eclist_bin(1),be2dec(-,2)],%[ssl_fc_ecformats_bin,be2dec(-,1)]
      http-request set-header X-SSL-JA3-Hash %[req.fhdr(x-ssl-ja3),digest(md5),hex]

Output:

request.headers.X-Ssl-Ja3: ,,,,
request.headers.X-Ssl-Ja3-Hash: E060AE38FB29E51244236DF770C21713

Has anyone else run into the same problems or is there something I need to enable first?
Thanks in advance for any replies!

The missing piece was the following global setting:

tune.ssl.capture-buffer-size 96