From Xojo Documentation
New in 2021r3
The scrollbar control.
A DesktopScrollbar can be either horizontal or vertical. To set its orientation programatically, set the height to be greater than the width for a vertical scrollbar. Set the width to be greater than the height for a horizontal scrollbar.
Changing the maximum value of a DesktopScrollbar at runtime:
Setting the text of a DesktopLabel, control to the value of the DesktopScrollbar when the user scrolls:
See also the discussion of scrolling DesktopListBox controls horizontally using a DesktopScrollbar control.