<select id="selectProgrammingLanguage">
    <option value="c">C</option>
    <option value="cpp">C++</option>
    <option value="java">JAVA</option>
    <option value="php">PHP</option>
    <option value="python">Python</option>
    <option value="dotNet">.Net</option>
    <option value="html">HTML</option>
    <option value="css">CSS</option>
    <option value="javascript">JavaScipt</option>
    <option value="react">React</option>
    <option value="angular">Angular</option>
    <option value="svelt">Svelt</option>
    <option value="vue">Vue</option>
    <option value="node">Node</option>
    <option value="wordpress">Wordpress</option>
</select>

selectBox = new vanillaSelectBox("#selectProgrammingLanguage", {
    "keepInlineStyles":true,
    "maxHeight": 200,
    "minWidth":678,
    "search": true,
    "placeHolder": "Choose..." 
});

<select id="frameworkCMS" multiple size="2" >
    <optgroup label="Javascript">
        <option>React</option>
        <option>Vue</option>
        <option>Angular</option>
        <option>Svelt</option>
    </optgroup>
    <optgroup label="Python">
        <option>Django</option>
        <option>Flask</option>
        <option>Bottle</option>
        <option>Web2Py</option>
        <option>CherryPy</option>
    </optgroup>
    <optgroup label="PHP">
        <option>Laravel</option>
        <option>CodeIgniter</option>
        <option>Symfony</option>
        <option>YII</option>
        <option>CakePHP</option>
    </optgroup>
</select>

let frameworkCMS = new vanillaSelectBox("#frameworkCMS", {
    "maxHeight": 400,
    "search": true,
    translations: { "all": "All", "items": "Selected" },
    "minWidth":178,
    "placeHolder": "Choose..." 
});

<select id="multipleSelect" multiple size="3">
    <option value="c">C</option>
    <option value="cpp">C++</option>
    <option value="java">JAVA</option>
    <option value="php">PHP</option>
    <option value="python">Python</option>
    <option value="dotNet">.Net</option>
    <option value="html">HTML</option>
    <option value="css">CSS</option>
    <option value="javascript">JavaScipt</option>
    <option value="react">React</option>
    <option value="angular">Angular</option>
    <option value="svelt">Svelt</option>
    <option value="vue">Vue</option>
    <option value="node">Node</option>
    <option value="wordpress">Wordpress</option>
</select>

selectBox3 = new vanillaSelectBox("#multipleSelect", {
    "minWidth":178,
    "maxHeight": 200,
    "search": true,
    "stayOpen":true
});