SweetAlert2 Disappearing when Triggered from Pressing Return

I am using a document.onkeydown to fire when Return is pressed when an element has been tabbed to:

Update:

function detectspecialkeys(e) {
  var evtobj=window.event? event : e; //distinguish between explicit event object (window.event) & implicit
  console.log('Event: ' , evtobj);
  console.log('Code: ' + evtobj.code);
  console.log('Repeat: ' + evtobj.repeat);
  if (evtobj.repeat) {return}
  if ((code==='Space') || (code==='Enter')) { // Space or Return (code:Enter)
    console.log('EObj-Sp/Return: ' , evtobj.target);
    if (evtobj.target.nodeName == 'BUTTON') {
      console.log('Inside Button'); // only see once
      var selid = '#' + evtobj.target.id;
    }
    $(#selid).trigger('singletap');
  }
}
document.onkeydown=detectspecialkeys;

I'm using jQuery Touch Events to handle interactions.

I'm using this version of Sweet Alert2: https://rahulbhut21.github.io/SweetAlert2/

I can see my handler firing and see the console.log ok:

$('#selid').on('singletap', function(e) {
  console.log('Inside Singletap'); // only see once
  e.preventDefault();
  swal('Test').catch(swal.noop);
  return false;  
});

When I click on #selid, the SweetAlert 2 alert shows fine, but when using the keyboard Return, it flashes and then disappears. I've tried to implement suggestions mentioned elsewhere, but the alert is still disappearing.

The detectspecialkeys function just needed:

evtobj.preventDefault();
evtobj.stopPropagation();

I believe this was needed as the click event was probably clicking outside of the SweetAlert modal on a parent, due to propagation and thus immediately closing it.