Taskbar Thumbnails -on hover

KDE’s Taskbar Thumbnails still do not function. Last time this worked properly was KDE 4.7.4
KDE should resolve this upstream (now 4.10.5). I’d rather not use the icon-only task manager. If any developers see this please consider fixing the bug. Thanks.

System Settings >Desktop Effects >All Effects >Taskbar Thumbnails
(Combined with taskbar grouping, by program)