JSFiddle - React, Tailwind, and code Playground

HTML

<select class="testSelect">
    <option value="test1">test1</option>
    <option value="test2">test2</option>
    <option value="test3">test3</option>
    <option value="test4">test4</option>
</select>

JavaScript

var select = document.querySelector(".testSelect");
var selectOption = select.options[select.selectedIndex];
var lastSelected = localStorage.getItem('select');

if(lastSelected) {
    select.value = lastSelected; 
}

select.onchange = function () {
   lastSelected = select.options[select.selectedIndex].value;
   console.log(lastSelected);
   localStorage.setItem('select', lastSelected);
}