JSFiddle - React, Tailwind, and code Playground

HTML

<input id="in1" />

JavaScript

$(function() {
   var firstval = ["five","six","seven","eight"];
    var obj =   $('#in1').autocomplete({
           source: firstval,
           minLength: 0
       }).focus(function(){
            var secondval = ["Banana", "Orange", "Apple", "Mango"];
             obj.autocomplete({
               source: secondval.concat(firstval),
               minLength: 0
           })           
          $(this).data("autocomplete").search($(this).val());
       });
   });