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    <label for="car-brands">Select a car brand and populate a hidden field. Also check the console for the array result.</label>
    <select id="car-brands" name="car_brands[]" multiple>
        <option value="volkswagen">Volkswagen</option>
        <option value="toyota">Toyota</option>
        <option value="ford">Ford</option>
        <option value="honda">Honda</option>
        <option value="chevrolet">Chevrolet</option>
    <input type="text" id="car_brands_list" name="car_brands_list" size="48" placeholder="Select options above...">

    Add new options to the dropdown. Add a new car brand and check the dropdown menu above.
    <input type="text" id="newOption" class="newOption" value="Aston Martin"> <button id="demo" onclick="addOption()">Add me</button>



                body {
    font-family: Inter, sans-serif;
    font-size: 16px;
button {
    font-family: inherit;
    font-size: inherit;
    padding: 8px 16px;


                document.addEventListener("DOMContentLoaded", (event) => {
    let mySelect ="#car-brands", {
        descriptions: true,
        hideSelected: true,
        hideDisabled: true,
        multiLimit: 5,
        multiShowCount: false,
        multiContainer: true,
    }).on('change', () => {
        const mySelectField = document.querySelector('select');
        const options = mySelectField.querySelectorAll('option:checked');

        console.log(Array.from(options, e => e.value));

        document.getElementById('car_brands_list').value = Array.from(options, e => e.value).join(', ');

        return Array.from(options, e => e.value);

    document.getElementById('demo').onclick = function() {

const slugify = str =>
    .replace(/[^\w\s-]/g, '')
    .replace(/[\s_-]+/g, '-')
    .replace(/^-+|-+$/g, '');

// Function to add a new option
function addOption() {
    let selectElement = document.querySelector('select');

    // Create a new option element
    const newOption = document.createElement("option");
    newOption.textContent = document.getElementById('newOption').value;
    newOption.value = slugify(document.getElementById('newOption').value);
    // Append the new option to the select element