Custom event, 2 clicks at a time

1. The custom event triggers the click event of .cpcstartrefresh, but triggers 2 click events each time

2. The code is as follows:
window.onmessage = function (e) {
/ / create an event object,

    var myEvent = document.createEvent("Event");
    myEvent.initEvent("click", false, false);
    e = e || event;
    e.eventType = "message";
    if (e.data === "returnfromsht") {
         console.log(e.data, "returnfromsht4");
         
         //2
         document.getElementsByClassName("cpcstartrefresh")[0].dispatchEvent(myEvent);
         
    } else if (e.data === "maximumwindow") {
        console.log(e.data, "maximumwindow");
    }
};
Feb.26,2021
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