Of course you can't, because it is all a result of the decision that only in-screen forms will be dockable. So re-applying the dockability to other types of forms would, it seems, require much more work on behalf of VFP Team. Since there's probably just a few of us who would yell to have this, I think chances are low to see it in this or next version.

Nevertheless, it would be really cool to have a VFP form dockable to anywhere on desktop. Even on top of any other open window on Windows desktop, eh?

>Hmmmmm.... but you can't change "ShowWindow" property for a form where you set "Dockable" property to 1 (Support docking and is dockable). and back, for "in-top" form you can't set Dockable property.. I have play a bit with forms,but did not there ways to Dock in-top form to not-in-screen form.
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>>And the limitation would make sense if _screen was the only possible docking port. But since forms can be docked on each other, I can easily see how we could build things using one form as a dock port for other forms, or even allow any form to dock on any other form, regardless of them being desktop or not, as-top or in-top forms.