JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.12/themes/ui-lightness/jquery-ui.css">
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.5.1/jquery.js"></script>
<script src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.12/jquery-ui.js"></script>
Select Week: <input id="selectWeek">

JavaScript

//replace  selectWeek with your date pickers id here at all places 
$(function() { //this is onload
$("#selectWeek")
      .datepicker(
      {
            firstDay : 1, // set first day of week as monday
            changeMonth : true, // provide option to select Month
            changeYear : true, // provide option to select year
            showButtonPanel : true, // button panel having today and done button
           
        onClose : function(dateText, inst) {
                  if ($(this).val() == "") {
                        return;
                  }
           
                  // below code will calculate the monday and set it in input box
                  var fromDate = $("#selectWeek").datepicker("getDate");
                  var date = fromDate.getDate();
                  var month = fromDate.getMonth() + 1;// +1 as jan is 0
                  var year = $(
                  "#ui-datepicker-div .ui-datepicker-year :selected").val();
     
                  if (fromDate.getDay() != 1) { // if not monday
                        if (fromDate.getDay() == 0) {// if sunday
                              date = date - 6;
                        } else {
                              date = date + (-fromDate.getDay() + 1);
                        }
                  }
                  var dateStr = month + "/" + date + "/" + year;
                  $(this).val(dateStr);
                  $(this).blur();// remove focus input box
        },
            duration : 0,

            onChangeMonthYear : function() {
                  setTimeout("applyWeeklyHighlight()", 100);
                  },// applyWeeklyHighlight is below
                  beforeShow : function() {
                        setTimeout("applyWeeklyHighlight()", 100);
                  }
            });
});//end of onload

/**
 * Set highhlight on the week on hover.
 */
function applyWeeklyHighlight() {
                       
      $('.ui-datepicker-calendar tr').each(function() {

      ...