JSFiddle - React, Tailwind, and code Playground

HTML

<html lang="en">
  <head>
    <!-- Required meta tags -->
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">

    <!-- Bootstrap CSS -->
<link
  rel="stylesheet"
  href="https://cdnjs.cloudflare.com/ajax/libs/selectize.js/0.15.2/css/selectize.default.min.css"
  integrity="sha512-pTaEn+6gF1IeWv3W1+7X7eM60TFu/agjgoHmYhAfLEU8Phuf6JKiiE8YmsNC0aCgQv4192s4Vai8YZ6VNM6vyQ=="
  crossorigin="anonymous"
  referrerpolicy="no-referrer"
/>
    <title>Selectize bug??</title>
  </head>
  <body>
       <div class="container">    
        <div class="row mb-4">
          <label for="OneTwo" class="col-sm-3 col-md-4 col-form-label"></label>
          <div class="col-sm-9 col-md-8">
            <select id="OneTwo" name="OneTwo">
              <option value="1">One</option>
              <option value="2">Two</option>
            </select>
          </div>
        </div>
        <div class="row mt-4">
          <label for="ThreeFour" class="col-sm-3 col-md-4 col-form-label"></label>
          <div class="col-sm-9 col-md-8">
            <select id="ThreeFour" name="ThreeFour">
              <option value="3">Three</option>
              <option value="4">Four</option>
            </select>
          </div>
        </div>

       </div>

    <!-- Optional JavaScript -->
    <!-- jQuery first, then Popper.js, then Bootstrap JS -->
    <script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>
<script
  src="https://cdnjs.cloudflare.com/ajax/libs/selectize.js/0.15.2/js/selectize.min.js"
  integrity="sha512-IOebNkvA/HZjMM7MxL0NYeLYEalloZ8ckak+NDtOViP7oiYzG5vn6WVXyrJDiJPhl4yRdmNAG49iuLmhkUdVsQ=="
  crossorigin="anonymous"
  referrerpolicy="no-referrer"
></script>
</body>
</html>

JavaScript

var debug1 = $("#OneTwo").selectize({ });
var debug2 = $("#ThreeFour").selectize({});