Set minLength 0, keyboard "Downward Arrow" not working find.

[reginna-chao]

Set minLength to 0. And I couldn't select the keyword, when I focused input and used "Downward Arrow".

Test JSFiddle

This my code:

<input type='text'
   placeholder='Programming language name'
   class='flexdatalist'
   list='languages'
   name='language'>

<datalist id="languages">
    <option value="PHP">PHP</option>
    <option value="JavaScript">JavaScript</option>
    <option value="Cobol">Cobol</option>
    <option value="C#">C#</option>
    <option value="C++">C++</option>
    <option value="Java">Java</option>
    <option value="Pascal">Pascal</option>
    <option value="FORTRAN">FORTRAN</option>
    <option value="Lisp">Lisp</option>
    <option value="Swift">Swift</option>
</datalist>
<script>
    $('.flexdatalist').flexdatalist({
        minLength: 0,
        maxShownResults: 10
    });
</script>

How could I fix this bug?