A [Ttk] (i.e. theme-able) [scrollbar] [widget].
    :   '''[ttk]::scrollbar''' ''pathName'' ?''options…''?
    :   http://www.tcl.tk/man/tcl/TkCmd/ttk_scrollbar.htm


**Layout names**

[HaO] 2019-04-29: The layouts are called: '''Horizontal.TScrollbar''' and '''Vertical.TScrollbar''':

======
% ttk::style layout Vertical.TScrollbar
Vertical.Scrollbar.trough -sticky ns -children {Vertical.Scrollbar.uparrow -side top -sticky {} Vertical.Scrollbar.downarrow -side bottom -sticky {} Vertical.Scrollbar.thumb -sticky nswe -unit 1 -children {Vertical.Scrollbar.grip -sticky {}}}
======


<<categories>> Widget