...
  const handleExecutionPhaseChanged = (phaseOutput: IExecutionPhaseOutput) => {
    switch (phaseOutput.executionPhase) {
      case ExecutionPhase.running:
        const log = [new Date().toISOString() + ' EXECUTION PHASE - RUNNING'];
        setExecutionLog(log);
        break;
      case ExecutionPhase.completed:
        setExecutionLog(executionLog => [
          ...executionLog,
          new Date().toISOString() +
            ' EXECUTION PHASE - COMPLETED and output ' +
            JSON.stringify(phaseOutput.outputModel?.toJSON()),
        ]);
        break;
      case ExecutionPhase.completed_with_error:
        setExecutionLog(executionLog => [
          ...executionLog,
          new Date().toISOString() +
            ' EXECUTION PHASE - COMPLETED_WITH_ERROR and output ' +
            JSON.stringify(phaseOutput.outputModel?.toJSON()),
        ]);
        break;
    }
  };

...
<Output
        autoRun={false}
        code={code}
        id={id}
        kernel={defaultKernel}
        executeTrigger={execTrigger}
        outputs={output ? output : []}
        onExecutionPhaseChanged={handleExecutionPhaseChanged}
        suppressCodeExecutionErrors={true}
        showEditor
      />