The following script displays a button and a single line listbox (= html select) which should extend to 100px width. But the listbox is rendered way too small in Firefox. It seems that the width of the "drop down arrow" isn't correctly calculated. Works fine in Chrome and Opera.

<vbox width="100px">
<button label="test" hflex="1"/>
<listbox rows="1" mold="select" hflex="1">
<listitem label="Inbox"/>
<listitem label="Received"/>
<listitem label="Draft"/>
</listbox>
</vbox>