closeFormPopup NG errors

In both NG and NGDesktopClient I do plugins.window.showFormPopup specifying the new parameters for 2020.12.0 (3622):

        var elementToShowRelatedTo = elements.button_accept_guest_of_member;
	var showBackdrop = true;
	var doNotCloseOnClickOutside = true;//user must use close button or cancel button - this way it acts like modal
	var scope = forms.PITC_0F_checkin_ng;//this form is for popup to write back data to a form var
	var dataproviderID = 'vf_dummy';
	var width = 650;
	var height = 250;
	var x = null;//use the element closest
	var y = null;//use the element closest
	var callback = postPaymentPopup;

        plugins.window.showFormPopup(elementToShowRelatedTo, forms.PITC_1F_checkin_payment_ng, scope, dataproviderID, width, height, x, y, showBackdrop, doNotCloseOnClickOutside, callback);

The form does popup correctly.
When a button on the popup form is clicked for cancel this is called:

plugins.window.cancelFormPopup();

At this point we get an error:

ERROR com.servoy.j2db.util.Debug - Error while executing client side code. Please see browser console for more info. Error: TypeError: event is undefined (Form Context: PITC_1F_checkin_payment_ng), JSEvent(type = action, source = Component: <‘button_cancel_form’ of parent FormUI for FormController[form: PITC_1F_checkin_payment_ng,…

java.lang.RuntimeException: Error while executing client side code. Please see browser console for more info. Error: TypeError: event is undefined
at org.sablo.websocket.WebsocketEndpoint.waitResponse(WebsocketEndpoint.java:581) ~[sablo_2020.12.0.3622.jar:?]

In the browser console we get this error:

TypeError: event is undefined
createJSEvent http://localhost:8183/js/servoy.js:299
cancelFormPopupInternal http://localhost:8183/servoyservices/wi … dow.js:330
cancelFormPopup http://localhost:8183/servoyservices/wi … dow.js:319
handleMessage http://localhost:8183/sablo/js/websocket.js:295
onmessage http://localhost:8183/sablo/js/websocket.js:705
ReconnectingWebSocket http://localhost:8183/sablo/lib/reconne … ket.js:179
onmessage http://localhost:8183/sablo/lib/reconne … ket.js:280
angular.js:15567:41

The createJsEvent code is this:

       createJSEvent: function (event, eventType, contextFilter, contextFilterElement) {
            var targetEl = event;
            if (event.target)
                targetEl = event.target;
            else if (event.srcElement)
                targetEl = event.srcElement;

If the user clicks on the other button on the popup form to close the form (save data) we get same error.
Note that the callback is never called.

If my usage of the showFormPopup and the closeFormPopup or cancelFormPopup is correct then I should make a Jira report.

Hello,

Please create a Jira case about this issue. Link this forum post.
If you have an example solution, please also add it to the case.

Thank you!

Made report:
https://support.servoy.com/browse/SVY-15737
I have not made a test solution yet.
I can if needed.