Forums Scripts & Popups Hsbar of list, what's the purpose?

What is purpose of this style? It won't get enabled even text goes over the list borders. Can someone tell me?

EDIT:
Forget this!
I found it with search, after I just noticed to choose "All posts".

here is an explain
if you load this testscript

Type /dialog -m test test


dialog test {
size -1 -1 200 100
option dbu
list 1,10 10 180 80,vsbar,hsbar
}
on 1:dialog:test:init:0:{ did -az $dname 1 this is an explain how you can enable the hsbar in list }

the secret is the -z

did -z dialogname id