Docking: Fixed dragging docked window with _NoMove flag (#2325)

imgui.cpp

@@ -5925,8 +5925,9 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
             // Docking: Dragging a dockable window (or any of its child) turns it into a drag and drop source.
             // We need to do this _before_ we overwrite window->DC.LastItemId below because BeginAsDockableDragDropSource() also overwrites it.
             if ((g.ActiveId == window->MoveId) && ((g.IO.ConfigDockingWithShift && g.IO.KeyShift) || (!g.IO.ConfigDockingWithShift)))
-                if ((window->RootWindow->Flags & (ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoDocking)) == 0)
-                    BeginAsDockableDragDropSource(window);
+                if ((window->Flags & ImGuiWindowFlags_NoMove) == 0)
+                    if ((window->RootWindow->Flags & (ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoDocking)) == 0)
+                        BeginAsDockableDragDropSource(window);
 
             // Docking: Any dockable window can act as a target. For dock node hosts we call BeginAsDockableDragDropTarget() in DockNodeUpdate() instead.
             if (g.DragDropActive && !(flags & ImGuiWindowFlags_NoDocking))