Popup windows will be hidden when we minimize a main frame or shown
when we maximize or restore a minimized main frame.

diff --git a/windows/nonclient.c b/windows/nonclient.c
index 0563c59..3788e47 100644
--- a/windows/nonclient.c
+++ b/windows/nonclient.c
@@ -2729,14 +2729,20 @@
 	break;
 
     case SC_MINIMIZE:
+        if (hwnd == GetForegroundWindow())
+            ShowOwnedPopups(hwnd,FALSE);
 	ShowWindow( hwnd, SW_MINIMIZE ); 
 	break;
 
     case SC_MAXIMIZE:
+        if (IsIconic(hwnd) && hwnd == GetForegroundWindow())
+            ShowOwnedPopups(hwnd,TRUE);
 	ShowWindow( hwnd, SW_MAXIMIZE );
 	break;
 
     case SC_RESTORE:
+        if (IsIconic(hwnd) && hwnd == GetForegroundWindow())
+            ShowOwnedPopups(hwnd,TRUE);
 	ShowWindow( hwnd, SW_RESTORE );
 	break;