diff --git a/lcl/interfaces/qt6/qtobject.inc b/lcl/interfaces/qt6/qtobject.inc
index 1a7af357c7..0f0517be14 100644
--- a/lcl/interfaces/qt6/qtobject.inc
+++ b/lcl/interfaces/qt6/qtobject.inc
@@ -508,7 +508,7 @@ procedure TQtWidgetSet.AppSetTitle(const ATitle: string);
 var
   W: WideString;
 begin
-  W := GetUtf8String(ATitle);
+  W := {%H-}ATitle;
   QCoreApplication_setApplicationName(@W);
 end;
 
diff --git a/lcl/interfaces/qt6/qtobjects.pas b/lcl/interfaces/qt6/qtobjects.pas
index 5911add009..43f7349ddf 100644
--- a/lcl/interfaces/qt6/qtobjects.pas
+++ b/lcl/interfaces/qt6/qtobjects.pas
@@ -1724,7 +1724,7 @@ procedure TQtFont.setFamily(p1: string);
 var
   Str: WideString;
 begin
-  Str := GetUtf8String(p1);
+  Str := {%H-}p1;
 
   QFont_setFamily(FHandle, @Str);
 end;
@@ -4985,7 +4985,7 @@ procedure TQtStringList.Insert(Index: Integer; const S: string);
 var
   W: WideString;
 begin
-  W := GetUtf8String(S);
+  W := {%H-}S;
   QStringList_insert(FHandle, Index, @W);
 end;
 
diff --git a/lcl/interfaces/qt6/qtpagecontrol.inc b/lcl/interfaces/qt6/qtpagecontrol.inc
index 21dcbb8614..87487148c2 100644
--- a/lcl/interfaces/qt6/qtpagecontrol.inc
+++ b/lcl/interfaces/qt6/qtpagecontrol.inc
@@ -298,8 +298,7 @@ begin
   QtTabWidget.setUpdatesEnabled(False);
   QtTabWidget.BeginUpdate;
   try
-    QtTabWidget.insertTab(AIndex, TQtPage(AChild.Handle).Widget,
-      GetUtf8String(AChild.Caption));
+    QtTabWidget.insertTab(AIndex, TQtPage(AChild.Handle).Widget, AChild.Caption{%H-});
   finally
     QtTabWidget.EndUpdate;
     QtTabWidget.setUpdatesEnabled(True);
@@ -489,7 +488,7 @@ begin
   Index := AChild.PageIndex;
   if Index < 0 then
     Index := ATabControl.IndexOf(AChild);
-  TQtTabWidget(ATabControl.Handle).setTabText(Index, GetUtf8String(AText));
+  TQtTabWidget(ATabControl.Handle).setTabText(Index, AText{%H-});
 end;
 
 class procedure TQtWSCustomTabControl.SetTabPosition(
diff --git a/lcl/interfaces/qt6/qtprivate.pp b/lcl/interfaces/qt6/qtprivate.pp
index 42d06032b8..b1fbd3ba55 100644
--- a/lcl/interfaces/qt6/qtprivate.pp
+++ b/lcl/interfaces/qt6/qtprivate.pp
@@ -170,7 +170,7 @@ begin
   TextEdit := TQtTextEdit(FOwner.Handle);
   if ABlockSignals then
     TextEdit.BeginUpdate;
-  W := GetUtf8String(AStr);
+  W := AStr;
   if AClear then
   begin
     // never trigger changed signal when clearing text here.
@@ -276,7 +276,7 @@ begin
   {$endif}
   if FTextChanged then InternalUpdate;
   FStringList[Index] := S;
-  W := GetUTF8String(S);
+  W := {%H-}S;
   TQtTextEdit(FOwner.Handle).setLineText(Index, W);
 end;
 
@@ -288,7 +288,7 @@ begin
   WriteLn('TQtMemoStrings.SetTextStr Value=',Value);
   {$endif}
   SetInternalText(Value);
-  W := GetInternalText;
+  W := {%H-}GetInternalText;
   ExternalUpdate(W, True, False);
   FTextChanged := False;
 end;
@@ -432,9 +432,9 @@ begin
   begin
     Index := FStringList.Add(S);
     if FHasTrailingLineBreak then
-      W := GetUTF8String(S + LineBreak)
+      W := UTF8ToUTF16(S + LineBreak)
     else
-      W := GetUTF8String(S);
+      W := UTF8ToUTF16(S);
     if FHasTrailingLineBreak then
     begin
       //issue #39444
@@ -452,7 +452,7 @@ begin
   end else
   begin
     FStringList.Insert(Index, S);
-    W := GetUTF8String(S);
+    W := UTF8ToUTF16(S);
     TQtTextEdit(FOwner.Handle).insertLine(Index, W);
   end;
   FTextChanged := False; // FStringList is already updated, no need to update from WS.
diff --git a/lcl/interfaces/qt6/qtproc.pp b/lcl/interfaces/qt6/qtproc.pp
index 39dda4aafe..3660c4167e 100644
--- a/lcl/interfaces/qt6/qtproc.pp
+++ b/lcl/interfaces/qt6/qtproc.pp
@@ -46,7 +46,6 @@ type
 
 
 procedure FillStandardDescription(var Desc: TRawImageDescription);
-function GetUtf8String(const S: String): WideString;
 
 implementation
 
@@ -91,9 +90,4 @@ begin
 //  Desc.MaskShift := 0;
 end;
 
-function GetUtf8String(const S: String): WideString;
-begin
-  Result := UTF8ToUTF16(S);
-end;
-
 end.
diff --git a/lcl/interfaces/qt6/qtsystemtrayicon.pas b/lcl/interfaces/qt6/qtsystemtrayicon.pas
index f96c24446a..ea2e6cb035 100644
--- a/lcl/interfaces/qt6/qtsystemtrayicon.pas
+++ b/lcl/interfaces/qt6/qtsystemtrayicon.pas
@@ -340,8 +340,8 @@ var
   WHint: WideString;
   WTitle: WideString;
 begin
-  WHint := GetUTF8String(AHint);
-  WTitle := GetUTF8String(ATitle);
+  WHint := {%H-}AHint;
+  WTitle := {%H-}ATitle;
   QSystemTrayIcon_showMessage(QSystemTrayIconH(TheObject), @WTitle, @WHint, AFlag, ATimeOut);
 end;
 
diff --git a/lcl/interfaces/qt6/qtthemes.pas b/lcl/interfaces/qt6/qtthemes.pas
index 8c57fa18f5..b870cf8f3d 100644
--- a/lcl/interfaces/qt6/qtthemes.pas
+++ b/lcl/interfaces/qt6/qtthemes.pas
@@ -617,7 +617,7 @@ begin
   case Details.Element of
     teToolTip:
       begin
-        W := GetUTF8String(S);
+        W := {%H-}S;
         Context.save;
         AOldMode := Context.SetBkMode(TRANSPARENT);
         try
@@ -661,7 +661,7 @@ begin
             exit;
           end;
 
-          W := GetUTF8String(S);
+          W := {%H-}S;
           Context.save;
           try
             Context.SetBkMode(TRANSPARENT);
@@ -712,7 +712,7 @@ begin
 
     else
     begin // default text drawing for all !
-      W := GetUTF8String(S);
+      W := {%H-}S;
       Context.save;
       AOldMode := Context.SetBkMode(TRANSPARENT);
       if Context.Parent <> nil then
diff --git a/lcl/interfaces/qt6/qtwinapi.inc b/lcl/interfaces/qt6/qtwinapi.inc
index 3df2c6f4de..a4864fb42e 100644
--- a/lcl/interfaces/qt6/qtwinapi.inc
+++ b/lcl/interfaces/qt6/qtwinapi.inc
@@ -1373,9 +1373,9 @@ begin
   QtDC :=TQtDeviceContext(DC);
 
   if Count >= 0 then
-    WideStr := GetUtf8String(Copy(Str, 1, Count))
+    WideStr := {%H-}Copy(Str, 1, Count)
   else
-    WideStr := GetUtf8String(Str);
+    WideStr := Str;
 
   ClipRect := Rect(0, 0, 0, 0);
   B := QtDC.getClipping;
@@ -2188,16 +2188,12 @@ var
     while CurCount > 0 do
     begin
       CharLen := UTF8CodepointSize(CurStr);
+      W := {%H-}Copy(CurStr, 1, CharLen);
       if AClipped then
-      begin
-        W := GetUTF8String(Copy(CurStr, 1, CharLen));
         QtDC.drawText(CurX, Y, Rect^.Right - Rect^.Left, Rect^.Bottom - Rect^.Top,
-          QtTextDontClip, @W);
-      end else
-      begin
-        W := GetUTF8String(Copy(CurStr, 1, CharLen));
+          QtTextDontClip, @W)
+      else
         QtDC.drawText(CurX, Y, @W);
-      end;
       inc(CurX, CurDx^);
       inc(CurDx);
       inc(CurStr, CharLen);
@@ -2218,9 +2214,9 @@ begin
   if ((Options and (ETO_OPAQUE + ETO_CLIPPED)) <> 0) and (Rect = nil) then
   begin
     if Count >= 0 then
-      WideStr := GetUtf8String(Copy(Str, 1, Count))
+      WideStr := {%H-}Copy(Str, 1, Count)
     else
-      WideStr := GetUtf8String(Str);
+      WideStr := Str;
 
     R := QtDC.getClipRegion.getBoundingRect;
     QtDC.font.Metrics.boundingRect(@R1, @R, 0, @WideStr);
@@ -2242,9 +2238,9 @@ begin
     if Options and ETO_RTLREADING <> 0 then
       QPainter_setLayoutDirection(QtDC.Widget, QtRightToLeft);
     if Count >= 0 then
-      WideStr := GetUtf8String(Copy(Str, 1, Count))
+      WideStr := {%H-}Copy(Str, 1, Count)
     else
-      WideStr := GetUtf8String(Str);
+      WideStr := Str;
 
     if (Options and ETO_CLIPPED <> 0) then
     begin
@@ -4217,7 +4213,7 @@ begin
     if Str = nil then
       AStr := ''
     else
-      AStr := GetUtf8String(Str);
+      AStr := Str;
     Size.cx := 0;
     Size.cY := Font.Metrics.Height;
     if (AStr = '') then
@@ -4304,7 +4300,7 @@ begin
   Size.cy := 0;
   if (Count <= 0) or (Str = nil) or (StrPas(Str) = '') then
     exit;
-  WideStr := GetUtf8String(Str);
+  WideStr := {%H-}Str;
   {$warning fixme Qt6}
   Size.cx := QtDC.Metrics.width(@WideStr, Count);
   Size.cy := QtDC.Metrics.height;
@@ -4552,6 +4548,7 @@ begin
 
   if (TQtWidget(Handle) is TQtMainWindow) and (not TQtMainWindow(Handle).IsMdiChild) then
   begin
+    ARect := Rect(0,0,0,0);
     GetClientRect(Handle, ARect);
     Width := ARect.Width;
     Height := ARect.Height;
@@ -5228,8 +5225,8 @@ var
   {$ENDIF}
 begin
   Result := 0;
-  Str := GetUtf8String(lpText);
-  TitleStr := GetUtf8String(lpCaption);
+  Str := lpText;
+  TitleStr := lpCaption;
   //TODO: TRANSLATIONS for buttons text, use TQtMessageBox
   if HWND <> 0 then
     AParent := TQtWidget(Hwnd).Widget
@@ -7250,9 +7247,9 @@ begin
   if not IsValidDC(DC) then Exit;
 
   if Count >= 0 then
-    WideStr := GetUtf8String(Copy(Str, 1, Count))
+    WideStr := {%H-}Copy(Str, 1, Count)
   else
-    WideStr := GetUtf8String(Str);
+    WideStr := Str;
 
   TQtDeviceContext(DC).drawText(X, Y, @WideStr);
 
diff --git a/lcl/interfaces/qt6/qtwscomctrls.pp b/lcl/interfaces/qt6/qtwscomctrls.pp
index f1761b4e25..c5db8532d4 100644
--- a/lcl/interfaces/qt6/qtwscomctrls.pp
+++ b/lcl/interfaces/qt6/qtwscomctrls.pp
@@ -571,7 +571,7 @@ begin
   ClearPanels(Widget);
   if AStatusBar.SimplePanel then
   begin
-    Str := GetUtf8String(AStatusBar.SimpleText);
+    Str := AStatusBar{%H-}.SimpleText;
     Widget.showMessage(@Str);
   end else
   if AStatusBar.Panels.Count > 0 then
@@ -580,7 +580,7 @@ begin
     SetLength(Widget.Panels, AStatusBar.Panels.Count);
     for i := 0 to AStatusBar.Panels.Count - 1 do
     begin
-      Str := GetUtf8String(AStatusBar.Panels[i].Text);
+      Str := AStatusBar{%H-}.Panels[i].Text;
       Widget.Panels[i] := TQtStatusBarPanel.CreateFrom(AStatusBar,
         QLabel_create(@Str, Widget.Widget));
       Widget.Panels[i].HasPaint := AStatusBar.Panels[i].Style = psOwnerDraw;
@@ -633,7 +633,7 @@ begin
   if AStatusBar.SimplePanel then
   begin
     ClearPanels(QtStatusBar);
-    Str := GetUtf8String(AStatusBar.SimpleText);
+    Str := AStatusBar{%H-}.SimpleText;
     QtStatusBar.showMessage(@Str);
   end else
   if AStatusBar.Panels.Count > 0 then
@@ -643,7 +643,7 @@ begin
     if (PanelIndex >= Low(QtStatusBar.Panels)) and
       (PanelIndex <= High(QtStatusBar.Panels)) then
     begin
-      Str := GetUtf8String(AStatusBar.Panels[PanelIndex].Text);
+      Str := AStatusBar{%H-}.Panels[PanelIndex].Text;
       QLabel_setText(QLabelH(QtStatusBar.Panels[PanelIndex].Widget), @Str);
       QLabel_setAlignment(QLabelH(QtStatusBar.Panels[PanelIndex].Widget),
         AlignmentToQtAlignmentMap[AStatusBar.Panels[PanelIndex].Alignment]);
@@ -663,14 +663,14 @@ begin
   QtStatusBar := TQtStatusBar(AStatusBar.Handle);
   if AStatusBar.SimplePanel then
   begin
-    Str := GetUtf8String(AStatusBar.SimpleText);
+    Str := AStatusBar{%H-}.SimpleText;
     QtStatusBar.showMessage(@Str);
   end else
   begin
     if (PanelIndex >= Low(QtStatusBar.Panels)) and
       (PanelIndex <= High(QtStatusBar.Panels)) then
     begin
-      Str := GetUtf8String(AStatusBar.Panels[PanelIndex].Text);
+      Str := AStatusBar{%H-}.Panels[PanelIndex].Text;
       QLabel_setText(QLabelH(QtStatusBar.Panels[PanelIndex].Widget), @Str);
     end;
   end;
@@ -815,7 +815,7 @@ begin
     TWIChild := QTreeWidgetItem_create(Ord(QTreeWidgetItemType));
     QTreeWidgetItem_setFlags(TWIChild, QtItemIsEnabled);
     QTreeWidgetItem_addChild(TWI, TWIChild);
-    Str := GetUtf8String(ALV.Column[AIndex].Caption);
+    Str := ALV{%H-}.Column[AIndex].Caption;
     QTreeWidgetItem_setText(TWI, AIndex, @Str);
   end;
 
@@ -990,7 +990,7 @@ begin
   TWI := QtTreeWidget.headerItem;
   if TWI <> NiL then
   begin
-    Str := GetUtf8String(ACaption);
+    Str := {%H-}ACaption;
     QTreeWidgetItem_setText(TWI, AIndex, @Str);
   end;
 end;
@@ -1524,7 +1524,7 @@ begin
     QtTreeWidget := TQtTreeWidget(ALV.Handle);
     TWI := QTreeWidgetItem_create(Ord(QTreeWidgetItemType));
     if AItem.Caption <> '' then
-      Str := GetUtf8String(AItem.Caption)
+      Str := AItem{%H-}.Caption
     else
       Str := '';
 
@@ -1552,7 +1552,7 @@ begin
         AAlignment := AlignmentToQtAlignmentMap[ALV.Column[i + 1].Alignment] or QtAlignVCenter;
       if AItem.Subitems.Strings[i] <> '' then
       begin
-        Str := GetUtf8String(AItem.Subitems.Strings[i]);
+        Str := AItem{%H-}.Subitems.Strings[i];
         QtTreeWidget.setItemText(TWI, i + 1, Str, AAlignment);
         QtTreeWidget.setItemData(TWI, i + 1, AItem);
       end;
@@ -1594,7 +1594,7 @@ begin
   end else
   begin
     QtTreeWidget := TQtTreeWidget(ALV.Handle);
-    Str := GetUtf8String(AText);
+    Str := {%H-}AText;
     TWI := QtTreeWidget.topLevelItem(AIndex);
     if TWI <> NiL then
     begin
@@ -2075,7 +2075,7 @@ begin
     for i := 0 to AList.Items.Count - 1 do
     begin
       AItem := AList.Items[i];
-      WStr := GetUTF8String(AItem.Caption);
+      WStr := AItem{%H-}.Caption;
       Item := QtTreeWidget.topLevelItem(i);
       QtTreeWidget.setItemText(Item, 0, WStr, AlignmentToQtAlignmentMap[AList.Column[0].Alignment]);
       QtTreeWidget.setItemData(Item, 0, AItem);
@@ -2113,7 +2113,7 @@ begin
         AAlignment := QtAlignLeft;
         if (TCustomListViewHack(AList).Columns.Count > 0) and (j + 1 < TCustomListViewHack(AList).Columns.Count) then
           AAlignment := AlignmentToQtAlignmentMap[TCustomListViewHack(AList).Column[j + 1].Alignment];
-        WStr := GetUtf8String(AItem.Subitems.Strings[j]);
+        WStr := AItem{%H-}.Subitems.Strings[j];
         QtTreeWidget.setItemText(Item, j + 1, WStr, AAlignment);
         QtTreeWidget.setItemData(Item, j + 1, AItem);
       end;
diff --git a/lcl/interfaces/qt6/qtwscontrols.pp b/lcl/interfaces/qt6/qtwscontrols.pp
index 875668c029..04ac2152dc 100644
--- a/lcl/interfaces/qt6/qtwscontrols.pp
+++ b/lcl/interfaces/qt6/qtwscontrols.pp
@@ -360,7 +360,7 @@ begin
     Exit;
   Wdgt := TQtWidget(AWinControl.Handle);
   Wdgt.BeginUpdate;
-  Wdgt.setText(GetUtf8String(AText));
+  Wdgt.setText(AText{%H-});
   Wdgt.EndUpdate;
 end;
 
diff --git a/lcl/interfaces/qt6/qtwsdialogs.pp b/lcl/interfaces/qt6/qtwsdialogs.pp
index 1e4ca681b3..aa5d82b3fc 100644
--- a/lcl/interfaces/qt6/qtwsdialogs.pp
+++ b/lcl/interfaces/qt6/qtwsdialogs.pp
@@ -284,10 +284,10 @@ begin
     // Remember that AFileDialog.FilterIndex is a 1-based index and that
     // List has a zero-based index
     if (AFileDialog.FilterIndex > 0) and (List.Count >= AFileDialog.FilterIndex) then
-      ASelectedFilter := GetUTF8String(List.Strings[AFileDialog.FilterIndex - 1])
+      ASelectedFilter := List{%H-}.Strings[AFileDialog.FilterIndex - 1]
     else
     if (List.Count > 0) then
-      ASelectedFilter := GetUTF8String(List.Strings[0]);
+      ASelectedFilter := List{%H-}.Strings[0];
 
   finally
     List.Free;
@@ -296,7 +296,7 @@ begin
   if (AFileDialog is TSaveDialog) and (trim(TmpFilter)='()') then
     Result := ''
   else
-    Result := GetUtf8String(TmpFilter);
+    Result := {%H-}TmpFilter;
 end;
 
 class procedure TQtWSFileDialog.UpdateProperties(
@@ -308,7 +308,7 @@ var
   {$ENDIF}
   s: String;
 begin
-  ATitle := GetUtf8String(AFileDialog.Title);
+  ATitle := AFileDialog{%H-}.Title;
   QtFileDialog.setWindowTitle(@ATitle);
 
   {$ifndef QT_NATIVE_DIALOGS}
@@ -359,7 +359,7 @@ begin
   if (AFileDialog.FileName <> '') and
     not DirectoryExistsUTF8(AFileDialog.FileName) then
   begin
-    ATitle := GetUTF8String(AFileDialog.FileName);
+    ATitle := AFileDialog{%H-}.FileName;
     if (AFileDialog is TSaveDialog) or FileExistsUTF8(AFileDialog.FileName) then
       QFileDialog_selectFile(QFileDialogH(QtFileDialog.Widget), @ATitle);
     {$ifndef QT_NATIVE_DIALOGS}
@@ -684,7 +684,7 @@ var
   AInitDir: WideString;
   s: String;
 begin
-  ATitle := GetUtf8String(AFileDialog.Title);
+  ATitle := AFileDialog{%H-}.Title;
   QtFileDialog.setWindowTitle(@ATitle);
   {$ifndef QT_NATIVE_DIALOGS}
   s := AFileDialog.InitialDir;
@@ -700,7 +700,7 @@ begin
   end;
   if not DirectoryExistsUTF8(S) then
     S := GetCurrentDirUTF8;
-  QtFileDialog.setDirectory(GetUTF8String(s));
+  QtFileDialog.setDirectory(S{%H-});
   {$else}
   S := AFileDialog.InitialDir;
   if not DirectoryExistsUTF8(S) then
diff --git a/lcl/interfaces/qt6/qtwsextctrls.pp b/lcl/interfaces/qt6/qtwsextctrls.pp
index 72c1011b6f..c21e77a806 100644
--- a/lcl/interfaces/qt6/qtwsextctrls.pp
+++ b/lcl/interfaces/qt6/qtwsextctrls.pp
@@ -209,7 +209,7 @@ begin
   QtGroupBox := TQtGroupBox.Create(AWinControl, AParams);
   QtGroupBox.GroupBoxType := tgbtRadioGroup;
 
-  Str := GetUtf8String(AWinControl.Caption);
+  Str := AWinControl{%H-}.Caption;
   QGroupBox_setTitle(QGroupBoxH(QtGroupBox.Widget), @Str);
 
   QtGroupBox.AttachEvents;
@@ -235,7 +235,7 @@ begin
   QtGroupBox := TQtGroupBox.Create(AWinControl, AParams);
   QtGroupBox.GroupBoxType := tgbtCheckGroup;
 
-  Str := GetUtf8String(AWinControl.Caption);
+  Str := AWinControl{%H-}.Caption;
   QGroupBox_setTitle(QGroupBoxH(QtGroupBox.Widget), @Str);
 
   QtGroupBox.AttachEvents;
diff --git a/lcl/interfaces/qt6/qtwsforms.pp b/lcl/interfaces/qt6/qtwsforms.pp
index dc906b6759..e1af7e2fac 100644
--- a/lcl/interfaces/qt6/qtwsforms.pp
+++ b/lcl/interfaces/qt6/qtwsforms.pp
@@ -205,7 +205,7 @@ begin
   QtMainWindow.QtFormBorderStyle := Ord(AForm.BorderStyle);
   QtMainWindow.QtFormStyle := Ord(AForm.FormStyle);
 
-  Str := GetUtf8String(AWinControl.Caption);
+  Str := AWinControl{%H-}.Caption;
 
   QtMainWindow.SetWindowTitle(@Str);
 
diff --git a/lcl/interfaces/qt6/qtwsmenus.pp b/lcl/interfaces/qt6/qtwsmenus.pp
index 2a061d0692..ec54144d37 100644
--- a/lcl/interfaces/qt6/qtwsmenus.pp
+++ b/lcl/interfaces/qt6/qtwsmenus.pp
@@ -112,7 +112,7 @@ begin
   Result.setHasSubmenu(AMenuItem.Count > 0);
   if not AMenuItem.IsLine then
   begin
-    Result.setText(GetUtf8String(AMenuItem.Caption));
+    Result.setText(AMenuItem.Caption{%H-});
     Result.setEnabled(AMenuItem.Enabled);
 
     {issue #37741}
@@ -283,7 +283,7 @@ begin
     if ACaption = cLineCaption then
       TQtMenu(Widget).setText('')
     else
-      TQtMenu(Widget).setText(GetUtf8String(ACaption));
+      TQtMenu(Widget).setText(ACaption{%H-});
   end;
 end;
 
diff --git a/lcl/interfaces/qt6/qtwsstdctrls.pp b/lcl/interfaces/qt6/qtwsstdctrls.pp
index 3d0eae354a..439a715613 100644
--- a/lcl/interfaces/qt6/qtwsstdctrls.pp
+++ b/lcl/interfaces/qt6/qtwsstdctrls.pp
@@ -756,7 +756,7 @@ var
 begin
   if not WSCheckHandleAllocated(ACustomMemo, 'AppendText') or (Length(AText) = 0) then
     Exit;
-  AStr := GetUtf8String(AText);
+  AStr := {%H-}AText;
   TQtTextEdit(ACustomMemo.Handle).BeginUpdate;
   TQtTextEdit(ACustomMemo.Handle).Append(AStr);
   TQtTextEdit(ACustomMemo.Handle).EndUpdate;
@@ -1390,7 +1390,7 @@ begin
   Text := TCustomComboBox(AWinControl).Text;
   QtComboBox.FList.Assign(TCustomComboBox(AWinControl).Items);
   QtComboBox.setCurrentIndex(ItemIndex);
-  QtComboBox.setText(GetUTF8String(Text));
+  QtComboBox.setText(Text{%H-});
   QtComboBox.setEditable((AParams.Style and CBS_DROPDOWN <> 0) or
     (AParams.Style and CBS_SIMPLE <> 0));