In 5.10 plasma adopted the scrollbar handling scheme from gnome 3. When clicking on the scrollbar the content is scrolled to the click position instead of scrolling a page in that direction. If there are several pages of content this makes navigation much harder. Regular Qt apps are not affected, just plasma.
cannot confirm with dolphin or gwenview 18.12.3.
Operating System: Arch Linux
KDE Plasma Version: 5.15.3
KDE Frameworks Version: 5.56.0
Qt Version: 5.12.2
ops, only plasma is affected. Sorry for noise.
*** Bug 441088 has been marked as a duplicate of this bug. ***