Fixes: #9623 Issue link: https://github.com/spring-projects/spring-integration/issues/9623 The `ConcurrentModificationException` is thrown from the `ThreadStatePropagationChannelInterceptor.MessageWithThreadState.stateQueue` which is a not thread-safe `LinkedList` * Fix `ThreadStatePropagationChannelInterceptor.MessageWithThreadState.stateQueue` to be a `LinkedBlockingQueue` instead **Auto-cherry-pick to `6.3.x` & `6.2.x`**