Internet Explorer 10 select list thick black border

Question

I've just upgraded to IE10 and noticed all my dropdown lists (select lists) when in "dropped down" state have a thick black border on them as below. I cant inspect the element using IE's built in tools so cant fix it! Can anyone assist?

Answer 1

While most of the various components of form elements are stylable in IE10, the popup in select elements can not be styled.