Office2000, Clippy can be decaptivated by the scrollbar

I tested reactos-bootcd-0.4.16-dev-116-g1643793-x86-gcc-lin-dbg
on VBox4.3.12 with VGAPNP/VBEMP driver (without guest additions)

• Install Office 2000
• launch Word
• you will see Clippy, the Office Assistent
• open the taskmgr in foreground
• now try the scroll the scrollbar in Word
  Clippy will be decaptivated by the scrollbar due to poor redrawing
  reactos-bootcd-0.4.16-dev-116-g1643793-x86-gcc-lin-dbg_clippyDecaptivated.webm
  reactos-bootcd-0.4.16-dev-116-g1643793-x86-gcc-lin-dbg_clippyDecaptivated.log

Yes, it is satisying to decaptivate Clippy, a good feeling for sure. But let's try to fix it anyway.