Using a scrollbar inside a popup element?

Hi everyone,
I'm creating a extension for mozilla firefox, and I need to have a 
volume-controler.
And I think a simple scrollbar would do the trick, but I wan't it only 
be visible when
I klick on a little button in the statusbar... So I created a popup 
element that
pops up when I click this button. But when i try to include a scrollbar 
in this popup,
mozilla crashes... So Im wondering, is it possible to put a scrollbar 
inside a popup,
if so how?

Yours,
Sven Andersson



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