I did some research and even made an illustrative patch.
Stride widgets are ‘transparent’ to clicks, which I think is not always convenient. Most importantly, I suspect that this is the reason why the drag and drop mechanism is not triggered.
WidgetsSkiaStrideImGui.vl (50.6 KB)
ImguiDragDrop.vl (101.0 KB)
I’d also like to point out that there is a problem with Skia LayerWidget - it draws on top of the window, not inside.