Test case (using konqueror icon view):
- The first icons are being shown (no scrollbar yet)
- When there is no space left, a vertical scrollbar is needed
- The vertical scrollbar may cover the right edge of the icons
(in the last column) => an horizontal scrollbar is needed :-(
Solution:
When using ScrollBarMode::Auto, prevent TQt from drawing icons on the
scrollbar area (before the scrollbar is shown).
Related to KDE bug #69589