Kate: how widen vertical scrollbar

<I've sent this to the kate (kwrite-devel) list with no response -- I thought 
I'd try here>

I'm asking about Kate 18.8.0 on Debian Buster.

I've turned off the Mini-Map and Preview on the vertical scrollbar (because I 
wasn't comfortable with them), but the scrollbar is too narrow.  Is there a 
way to widen it?

I've looked in katerc, but don't see a parameter there.  I've done a quick 
google which didn't turn up anything.