Description:

After upgrading Jenkins LTS from 2.479.1 to 2.541.2, all builds triggered via jenkins-cli.jar using the -s flag (wait for completion) are being aborted mid-run after the build has been running for a period of time. Builds triggered without -s complete successfully, confirming the issue is specific to the CLI wait/monitor behavior. 
 
The -f flag (stream console output) doesn't provide success or failure status. And due to our project restrictions websocket cli methods can't be used.

Steps to Reproduce:

1. Upgrade Jenkins LTS from 2.479.1 to 2.541.2
2. Trigger a long-running build using the CLI with the -s flag:

 
java.exe -jar jenkins-cli.jar -s https://<JENKINS_URL>/ -http -auth <USER>:<TOKEN> build <JOB_NAME> -s # Observe that the build starts successfully but is aborted after running for some time.

Expected Behavior:

The CLI should hold the connection open until the build completes and return the final build result (SUCCESS / FAILURE) with the appropriate exit code.

Actual Behavior:

The build is aborted mid-execution. The CLI disconnects an job aborted before the build finishes.
 
Started <JOB_NAME> #X
ERROR: null