How to regulate the scroll line amount in dolphin

on my laptop TUXEDO InfinityBook Pro running LEAP 15.4 KDE Argon
with these KDE repositries
when I scroll files in detailed view the scroll is too much, too many lines of scrolling, how can I regulate the amount of lines when I scroll?

Intermediate solution:

manythanks it works :smiley: :smiley:
P.S. wow, an only five years old bug