During the past few years, the "bar" on the right which controls the page position is a light gray, but the rest of the bar is the same color.

This makes it extremely difficult to find this bar handle with the mouse cursor to adjust the position of the page.

So how do you set this bar handle on the right hand side to a different color or contrast so that you can even see it to move it?

I am using just the default KDE desktop, and I am using Google Chrome browser.

But I have the same problem with all the browswers, if I recall correctly.