Distinguish event triggered by User or by jQuery (+ cloneEvent & EventProxy examples)

handle User & Manual click.js

const getCopy = obj => new Proxy(
    obj,
    {
        get: function( target, prop, receiver ) {
            let value = target[ prop ];
            /*copy array*/      if ( Array.isArray( value ) ) return value.slice( 0 );
            /*copy object*/     if ( typeof value === "object" && value.constructor.name === "Object" ) return Object.assign( {}, value );
            /*copy primitive*/  return value;
        }
    }
);
const cloneEvent = (event) => {
    function ClonedEvent(props){
        for(var x in props){
            this[x] = props[x];
        }
    }
    ClonedEvent.prototype = new Event(event.type, event);
    ClonedEvent.prototype.constructor = ClonedEvent;


    return new ClonedEvent(event);
}

//////////////////////////////////////////////////////////

function setModalUrl(event) {
    if (!event.isTrigger) return true;

    // expect an anchor <a>, in order to work with no-JS
    const $link = $(event.target);
    event.preventDefault();
    event.stopPropagation();

    const redirectModalError = event => {
        console.warn(
            'Unable to set the redirect URL in the modal. User will be redirected to a different domain without explicit notice. ' +
            'Please report this message to the administrators.'
        );
        $link.trigger('click');  // using `extraParameters` arg doesn't work here 🤷
        return false;
    }

    const $modalSelector = $link.data('containerid');
    const $modal = $($modalSelector);
    const $redirectTrigger = $modal.find('[data-js-redirect-url]')
    if ($redirectTrigger.length === 0) {
        return redirectModalError(event)
    }
    $redirectTrigger.each(el => {
        const $urlTarget = $(el);
        if ($urlTarget.is('form')) {
            $urlTarget.attr('action', $link.attr('href'));
        } else if ($urlTarget.is('a')) {
            $urlTarget.attr('href', $link.attr('href'));
        } else {
            console.log('no type');
            return redirectModalError(event)
        }
    });
};

$('.js-flyin-overlay-toggler').on('click', setModalUrl);