[Idea/v9] An easier way to customize the scrollbars' appearance

[idiotWu]

Discussed in #399

^{Originally posted by blitzve0 October 31, 2021}
Currently if we want to change the styling of the scroll bar thumb and tracks we have to overwrite the default styling from node modules. If basics settings like color transparency tracks color width padding etc could be set through config would be awesome

[katsar0v]

Some documentation will be great, the plugin is badly commented anyway.