diff --git a/minigui.d b/minigui.d
index f6d4838..491d526 100644
--- a/minigui.d
+++ b/minigui.d
@@ -3397,6 +3397,8 @@ class Window : Widget {
 			this.width = w;
 			this.height = h;
 			recomputeChildLayout();
+			version(win32_widgets)
+				InvalidateRect(hwnd, null, true);
 			redraw();
 		};