Source

<label for="dldemo">Favorite programming language:</label>
<input placeholder="Start typing…" list="dldemolist" id="dldemo">
<datalist id="dldemolist">
    <option value="Swift">
    <option value="Rust">
    <option value="Ruby">
    <option value="Python">
    <option value="PHP">
    <option value="Kotlin">
    <option value="JavaScript">
    <option value="Java">
    <option value="Go">
    <option value="C++">
    <option value="C#">C Sharp</option>
    <option value="C">
</datalist>