Having the same experience here on Ubuntu 22.04, and seems pretty consistent.
Last few lines from the 1P log at shutdown time (lines before that are from ~ 1 minute earlier):
ERROR 2024-06-17T15:56:17.899 tokio-runtime-worker(ThreadId(9)) [1P:native-messaging/op-native-core-integration/src/connection_handler.rs:62] message from b5x was None: EndConnection
ERROR 2024-06-17T15:56:17.899 tokio-runtime-worker(ThreadId(9)) [1P:native-messaging/op-native-core-integration/src/connection_handler.rs:31] Dropping connection with b5x due to error handling incoming message: EndConnection
ERROR 2024-06-17T15:56:23.454 ThreadId(86) [1P:op-crash-reporting/src/crash_handler.rs:257] Failed to prepare for requesting dump
Looking at the syslog, there is another message that seems of interest:
Jun 17 17:56:23 <hostname> kernel: [32256.606417] traps: ThreadPoolSingl[257649] trap invalid opcode ip:618d4344370a sp:7e0bfaff9500 error:0 in 1password[618d3f7ac000+837d000]
That appears few lines before the syslog log of the last logline from the 1P log:
Jun 17 17:56:23 <hostname> 1password.desktop[257638]: #033[1;38;5;196mERROR#033[0m #033[1;38;5;196m2024-06-17T15:56:23.454#033[0m ThreadId(86) [1P:op-crash-reporting/src/crash_handler.rs:257] #033[1;38;5;196mFailed to prepare for requesting dump#033[0m
This is all pretty late in the shutdown, e.g., the first kernel trap log is few lines after
Jun 17 17:56:23 <hostname> systemd[1]: Stopped target Multi-User System.
1P 8.10.34, Ubuntu 22.04.4 LTS, kernel 6.5.0-35-generic