Scrollbar up and down buttons issues

[medmedin2014]

There are 3 issues with scrollbar up and down buttons in FlatLaf v2.0.2:

1. The scrollbar up and down buttons are not well centered with the track
   
2. The scrollbar up and down buttons doesn't scale with scrollbar width
   
3. the scrollbar up and down buttons default size is too small and difficult to grab them by mouse
   

[DevCharly]

1 and 2 are fixed in main branch

regarding 3: there is now a new UI property ScrollBar.minimumButtonSize. Default is 12,12.

See also:

• https://www.formdev.com/flatlaf/components/scrollbar/
• https://www.formdev.com/flatlaf/customizing/#scrollbar

[medmedin2014]

They really look much better