How to change the scrollbar width in konsole?

Hi, I’m use Fedora Kde 42, breeze theme, a 4k external monitor 28” and the primary laptop screen at 2560x1600 resolution, all packages are updated.

The konsole scrollbar is tiny and the color is hard to see, see attached image.

How to increase the width and color of the scrollbar ? I tried to change the color in the konsole color scheme, but couldn’t find the one that sets the scrollbar.

Some searches suggests to change ~/.config/gtk-4.0/gtk.css, but it doesn’t work. I wouldn’t like to install klassy as that requires a build and installation.

Thanks for your time.

There are klassy RPM packages, I installed it and was to configure the scrollbar width, see attached screenshot of the scrollbar. You have to open klassy configuration → Application Style → Scrollbars (tab) → Groovy/Slider and increase the slider thickness, then in kde configuration you have to choose the klassy theming or the klassy application style.