diff --git a/packages/amunits/src/coreunits/intuition.pas b/packages/amunits/src/coreunits/intuition.pas
index caaad03a2d..a23ea2db12 100644
--- a/packages/amunits/src/coreunits/intuition.pas
+++ b/packages/amunits/src/coreunits/intuition.pas
@@ -4414,6 +4414,7 @@ begin
       WA_SizeGadget: NewWindow^.Flags := NewWindow^.Flags or WFLG_SIZEGADGET;
       WA_SmartRefresh: NewWindow^.Flags := NewWindow^.Flags or WFLG_SMART_REFRESH;
       WA_Activate: NewWindow^.Flags := NewWindow^.Flags or WFLG_ACTIVATE;
+      WA_Borderless: NewWindow^.Flags := NewWindow^.Flags or WFLG_BORDERLESS;
       WA_SuperBitMap: NewWindow^.BitMap := Pointer(TagList^.ti_Data);
       WA_Title: NewWindow^.Title := PChar(TagList^.ti_Data);
       WA_Top: NewWindow^.TopEdge := TagList^.ti_Data;