my stderr of tomcat is filling up with the following warning:
org.apache.coyote.http2.ConnectionSettingsBase.set Connection [40], An unknown 
setting with identifier [2147483647] and value [725733055] was ignored

It is related to http2 and is caused by Chrome (version 98 currently in use).
I could also catch a Wireshark dump for analysis.
After negotiating TLS the Chrome browser sends a settings frame.

This frame contains:

  *   Header table size
  *   Max concurrent streams
  *   Initial Windows size
  *   Max header list size
  *   Unknown: 0x8a fa = 35578
with value 0x2b 41 ce bf = 725733055

This warning always happens in the morning when users start working and open 
Chrome browser the first time.
During the day, this setting doesn't seem to be used any more.
Up to now I couldn't figure out, what this settings means. Wireshark doesn't 
know that setting, maybe it is some special feature of Chrome?

RFC https://datatracker.ietf.org/doc/html/rfc7540 says:

"The "HTTP/2 Settings" registry operates under the "Expert Review" policy

[RFC5226<https://datatracker.ietf.org/doc/html/rfc5226>] for values in the 
range from 0x0000 to 0xefff, with values

between and 0xf000 and 0xffff being reserved for Experimental Use."

The value 0x8afa lies not inside the reserved interval.


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