Yeah, I've seen that. It's (from memory) a little, umm, ugly. I also seem to remember it crashing wi I seem to remember that it doesn't support pinned collapsed windows either.

The docking window library I wrote is around 10 or so years old now, it pre-dates most of the other docking libraries I've found for Qt and I think some of them have only just supported the pinning behaviour, my implementation supported it from day 1!