Let me retract that. After playing a bit more, I noticed that
it was
not correctly changing the option after I selected something.
That problem seems to be with the tabindex="2" which I
suspected was
improper. The tabindex property should be on the control,
i.e. the
<select...> tag. You don't tab to the options, you tab
to the control.
Anyway, when I removed the tabindex="2" from all the options,
the
control worked correctly in Firefox.