Highlights usage of Hooks.onOperatorDebug() when ReactorDebugAgent.init() is called. Starting from Spring 2.2.0, if ReactorDebugAgent is in the classpath, and spring.reactor.debug-agent.enabled is true (by default, it is true) ReactorDebugAgent.init() is called automatically at startup. Using both Hooks.onOperatorDebug() and ReactorDebugAgent.init() cause doubled debugging stack frames, generated by Reactor. Also, Hooks.onOperatorDebug() can cause performance overhead.