diff --git a/lcl/interfaces/gtk/gtkwidgetset.inc b/lcl/interfaces/gtk/gtkwidgetset.inc
index 0eea2508ee..b9263116b2 100644
--- a/lcl/interfaces/gtk/gtkwidgetset.inc
+++ b/lcl/interfaces/gtk/gtkwidgetset.inc
@@ -1394,9 +1394,14 @@ begin
   begin
     FAppActive := AValue;
     if FAppActive then
-      Application.IntfAppActivate
-    else
+    begin
+      Application.IntfAppActivate;
+      AppRestoreStayOnTopFlags(False);
+    end else
+    begin
       Application.IntfAppDeactivate;
+      AppRemoveStayOnTopFlags(False);
+    end;
   end;
 end;
 
diff --git a/lcl/interfaces/gtk2/gtk2int.pas b/lcl/interfaces/gtk2/gtk2int.pas
index ca370c5c7c..4215973ca4 100644
--- a/lcl/interfaces/gtk2/gtk2int.pas
+++ b/lcl/interfaces/gtk2/gtk2int.pas
@@ -34,7 +34,7 @@ interface
 {$I gtkdefines.inc}
 
 uses
-  Types, Classes, SysUtils, Math,
+  Types, Classes, SysUtils, Math, maps,
   {$IfNDef GTK2_2}
     {$IfDef HasX}
      XLib, X, //XUtil,
@@ -52,6 +52,8 @@ type
   { TGtk2WidgetSet }
 
   TGtk2WidgetSet = class(TGtkWidgetSet)
+  private
+    StayOnTopList: TMap;
   protected
     procedure AppendText(Sender: TObject; Str: PChar);
     function GetText(Sender: TComponent; var Text: String): Boolean;
@@ -68,6 +70,8 @@ type
     procedure AppMinimize; override;
     procedure AppRestore; override;
     function AppHandle: THandle; override;
+    function AppRemoveStayOnTopFlags(const ASystemTopAlso: Boolean = False): Boolean; override;
+    function AppRestoreStayOnTopFlags(const ASystemTopAlso: Boolean = False): Boolean; override;
 
     procedure SetCallbackEx(const AMsg: LongInt; const AGTKObject: PGTKObject; const ALCLObject: TObject; Direct: Boolean);override;
     procedure SetCommonCallbacks(const AGTKObject: PGTKObject; const ALCLObject: TObject); override;
diff --git a/lcl/interfaces/gtk2/gtk2widgetset.inc b/lcl/interfaces/gtk2/gtk2widgetset.inc
index 031ee70163..9cda987273 100644
--- a/lcl/interfaces/gtk2/gtk2widgetset.inc
+++ b/lcl/interfaces/gtk2/gtk2widgetset.inc
@@ -565,6 +565,7 @@ end;
 constructor TGtk2WidgetSet.Create;
 begin
   inherited Create;
+  StayOnTopList := nil;
   im_context:=gtk_im_multicontext_new;
   g_signal_connect (G_OBJECT (im_context), 'commit',
     G_CALLBACK (@gtk_commit_cb), nil);
@@ -575,6 +576,11 @@ begin
   g_object_unref(im_context);
   im_context:=nil;
   im_context_widget:=nil;
+  if StayOnTopList <> nil then
+  begin
+    StayOnTopList.Free;
+    StayOnTopList := nil;
+  end;
   inherited Destroy;
 end;
 
@@ -653,6 +659,77 @@ begin
   {$endif}
 end;
 
+type
+  TGtk2TempFormStyleSet = Set of TFormStyle;
+const
+  TGtk2TopForms: Array[Boolean] of TGtk2TempFormStyleSet = (fsAllNonSystemStayOnTop,
+    fsAllStayOnTop);
+
+function TGtk2WidgetSet.AppRemoveStayOnTopFlags(const ASystemTopAlso: Boolean
+  ): Boolean;
+var
+  i: Integer;
+  AForm: TCustomForm;
+  W: PGtkWidget;
+  Flags: TGdkWindowState;
+begin
+  Result := True;
+  if StayOnTopList = nil then
+    StayOnTopList := TMap.Create(TMapIdType(ituPtrSize), SizeOf(TGtkWidget));
+  for i := 0 to Screen.CustomFormZOrderCount - 1 do
+  begin
+    AForm := Screen.CustomFormsZOrdered[i];
+    if AForm.HandleAllocated then
+    begin
+      W := PGtkWidget(AForm.Handle);
+      Flags := gdk_window_get_state(W^.Window);
+      if (AForm.Parent = nil) and
+        (AForm.FormStyle in TGtk2TopForms[ASystemTopAlso]) and
+         GTK_WIDGET_VISIBLE(W) and
+         not gtk_window_get_modal(PGtkWindow(W)) and
+         (Flags and GDK_WINDOW_STATE_ICONIFIED = 0) then
+      begin
+        gdk_window_set_keep_above(W^.Window, False);
+        if not StayOnTopList.HasId(W) then
+          StayOnTopList.Add(W, W);
+      end;
+    end;
+  end;
+end;
+
+function TGtk2WidgetSet.AppRestoreStayOnTopFlags(const ASystemTopAlso: Boolean
+  ): Boolean;
+var
+  i: Integer;
+  AForm: TCustomForm;
+  W: PGtkWidget;
+  Flags: TGdkWindowState;
+begin
+  Result := True;
+  if StayOnTopList = nil then
+    exit;
+  for i := Screen.CustomFormZOrderCount - 1 downto 0 do
+  begin
+    AForm := Screen.CustomFormsZOrdered[i];
+    if AForm.HandleAllocated then
+    begin
+      W := PGtkWidget(AForm.Handle);
+      Flags := gdk_window_get_state(W^.Window);
+      if (AForm.Parent = nil) and
+        (AForm.FormStyle in TGtk2TopForms[ASystemTopAlso]) and
+         GTK_WIDGET_VISIBLE(W) and
+         not gtk_window_get_modal(PGtkWindow(W)) and
+         (Flags and GDK_WINDOW_STATE_ICONIFIED = 0) then
+      begin
+        if StayOnTopList.HasId(W) then
+          gdk_window_set_keep_above(W^.Window, True);
+      end;
+    end;
+  end;
+  StayOnTopList.Free;
+  StayOnTopList := nil;
+end;
+
 {$IFDEF ASSERT_IS_ON}
   {$UNDEF ASSERT_IS_ON}
   {$C-}