datalist dropdown width

User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:33.0) Gecko/20100101 Firefox/33.0
Build ID: 20141011015303

Steps to reproduce:

See http://jsfiddle.net/stowball/b6axugr1/

Which is essentially this:

<input type="text" list="list" style="width: 90px;" />
<datalist id="list">
    <option>A normal length</option>
    <option>An even longer length</option>
    <option>A ridiculously large length muahahaha</option>
</datalist>


Actual results:

When you type, the options popup length is restricted to the width of the input and long options have an ellipsis. This makes searching for longer names much harder.


Expected results:

The option widths should not be truncated (to match Chrome & IE), and to match the behaviour of select options.