I was discomfited and confused to discover that "static" scroll boxes apparently don't contain scroll bars if the text area is larger than the box.
Given that they are, ahem, "scroll" boxes, this does not make sense.
I think that static scroll
boxes should work like Dashboard boxes. They should scroll as required.
You need to apply proper style, see my reply at TWiki:Plugins/TWikiDashboardAddOnDev