Found one Java-level deadlock:
=============================
"Handling GET /blue/organizations/jenkins/X/detail/X/2/pipeline/ from 10.1.0.2 : RequestHandlerThread[#125] BlueOceanUI/index.jelly PageStatePreloadDecorator/header.jelly":
  waiting to lock monitor 0x000000001faa3578 (object 0x00000000f6f07108, a org.jenkinsci.plugins.workflow.job.WorkflowRun),
  which is held by "WorkflowRun.copyLogs [#5] (Name #2)"
"WorkflowRun.copyLogs [#5] (Name #2)":
  waiting to lock monitor 0x0000000051b4ef48 (object 0x00000000f6f0f848, a org.jenkinsci.plugins.workflow.cps.CpsFlowExecution),
  which is held by "Running CpsFlowExecution[Owner[Name/2:Name #2]]"
"Running CpsFlowExecution[Owner[Name/2:Name #2]]":
  waiting to lock monitor 0x000000001faa3578 (object 0x00000000f6f07108, a org.jenkinsci.plugins.workflow.job.WorkflowRun),
  which is held by "WorkflowRun.copyLogs [#5] (Name #2)"

Found one Java-level deadlock:
=============================
"pool-26-thread-17":
  waiting for ownable synchronizer 0x00000000f05b3448, (a java.util.concurrent.locks.ReentrantLock$NonfairSync),
  which is held by "jenkins.util.Timer [#4]"
"jenkins.util.Timer [#4]":
  waiting to lock monitor 0x0000000022226e48 (object 0x00000000f3cfe998, a org.jenkinsci.plugins.workflow.job.WorkflowRun),
  which is held by "WorkflowRun.copyLogs [#2] (Name #3)"
"WorkflowRun.copyLogs [#2] (Name #3)":
  waiting to lock monitor 0x0000000026cf2778 (object 0x00000000f3cffcb0, a org.jenkinsci.plugins.workflow.cps.CpsFlowExecution),
  which is held by "Running CpsFlowExecution[Owner[Name/3:Name #3]]"
"Running CpsFlowExecution[Owner[Name/3:Name #3]]":
  waiting to lock monitor 0x0000000022226e48 (object 0x00000000f3cfe998, a org.jenkinsci.plugins.workflow.job.WorkflowRun),
  which is held by "WorkflowRun.copyLogs [#2] (Name #3)"