diff --git a/lcl/include/windowmagnet.inc b/lcl/include/windowmagnet.inc
index 8bb6cab728..a849d92494 100644
--- a/lcl/include/windowmagnet.inc
+++ b/lcl/include/windowmagnet.inc
@@ -202,6 +202,9 @@ begin
 
   for fi:= 0 to Screen.CustomFormCount - 1 do begin
     frm:= Screen.CustomForms[fi];
+    if not frm.Visible then continue;
+    if frm.WindowState=wsMinimized then continue;
+    if frm.HandleAllocated then continue;
     if frm.Handle = WindowPos.hwnd then continue;
     if not frm.SnapOptions.SnapFormTarget then continue;
     if GetWindowRect(frm.Handle, br) = 0 then continue;