Hello, can you please bring back the old design of the slider? Who came up with this strange new design with the pink bump???
Which old slider? The Slider from theme "Classic"?
Google, Apple, ...
You can change the thumbColor in the > Project Properties > Theming. Or use the SliderTools extension from @Ken: All Rescued Extensions From Inactive Communities - #83 by Salman_Dev
Change your theme to classic, then you will have the older look of components.
Maybe build your own sliders?
Canvas sliders can make informative scroll bars.