src/share/classes/javax/swing/PopupFactory.java

*** 201,216 ****
                  if (((JComponent)c).getClientProperty(
                              PopupFactory_FORCE_HEAVYWEIGHT_POPUP) == Boolean.TRUE) {
                      popupType = HEAVY_WEIGHT_POPUP;
                      break;
                  }
-             } else if (c instanceof Window) {
-                 Window w = (Window) c;
-                 if (!w.isOpaque() || w.getOpacity() < 1 || w.getShape() != null) {
-                     popupType = HEAVY_WEIGHT_POPUP;
-                     break;
-                 }
              }
              c = c.getParent();
          }
  
          return popupType;
--- 201,210 ----