docs: public boolean startInactivityTimer() {
          final boolean traceOn = TraceComponent.isAnyTracingEnabled();
  
          if (traceOn && tc.isEntryEnabled())
              Tr.entry(tc, "startInactivityTimer");
  
          if (_inactivityTimeout > 0
              && _status.getState() == TransactionState.STATE_ACTIVE
              && !_inactivityTimerActive) {
              EmbeddableTimeoutManager.setTimeout(this,
                                                  EmbeddableTimeoutManager.INACTIVITY_TIMEOUT, _inactivityTimeout);
              _inactivityTimerActive = true;
  
              _mostRecentThread.pop();
          }
  
          if (traceOn && tc.isEntryEnabled())
              Tr.exit(tc, "startInactivityTimer", _inactivityTimerActive);
          return _inactivityTimerActive;
      }