In case of let a = 'abc' (English), the input text is initialized. But, in case of let a = '돈까스' (Korean), the last letter remains as in the picture below.

$(function () {
    $('.input').on('input', clear);
});

let a = '돈까스';


function clear(event) {
    var Input_Text = event.currentTarget.value;
    if (a === Input_Text) {
        $('.input').val('');
        
    }
}

enter image description here