Changing a React Input Value from Vanilla Javascript

The short answer:

function setNativeValue(element, value) {
    let lastValue = element.value;
    element.value = value;
    let event = new Event("input", { target: element, bubbles: true });
    // React 15
    event.simulated = true;
    // React 16
    let tracker = element._valueTracker;
    if (tracker) {
        tracker.setValue(lastValue);
    }
    element.dispatchEvent(event);
}

var input = document.getElementById("ID OF ELEMENT");
setNativeValue(input, "VALUE YOU WANT TO SET");

Reference: https://stackoverflow.com/a/52486921/17360

The long answer:

React overrides the native Javascript onChange behavior. Triggering an onChange event does nothing to change the input field value in React’s eyes. To React the value is still unchanged, even though to a user the value can clearly be seen on the screen. The above code triggers the change in React also.