It's working correctly for me on Windows. But you seem to be on Mac... You should file a bug report then.
You can not see or grab the thumb until you scroll. If you stop, they disappear. I hate it, but it seems to be expected behavior.The term "hate" suggests that you need to know - this behavior is configurable.
Are you sure this is not just Mac functionality?
In Firefox, Messages, the Finder, or iTunes, for example, the scrollbar "thumbs" are not visible unless actively scrolling.
You can not see or grab the thumb until you scroll. If you stop, they disappear. I hate it, but it seems to be expected behavior.
I am playing with it today.
I have this construct many places
TPageControl (this may be nested under other controls, align alClient) > TTabSheet
In this I have
- TScrollBox(align alClient)
In scrollbox I then have
- TPanel (align AlTop)
That is the most simple construct. I am wondering if my problems (if you do not experience them) are related to TPageControl/TTabSheet and many nested controls. Still hard to understand how the scrollbox miscalculates its own area
... A really corny "fix" seems to be iterate all controls and then:
if (AControl is TPanel) and ( (AControl.Top = 0) and (AControl.Align = alTop) ) and (AControl.Parent is TScrollBox) and ( (AControl.Parent.Parent is TTabSheet) or (AControl.Parent.Parent is TPanel) ) then begin AControl.Height := AControl.Height + 65; end ;