diff --git a/lcl/interfaces/gtk3/gtk3lclintf.inc b/lcl/interfaces/gtk3/gtk3lclintf.inc
index eeef128c09..376ba347e7 100644
--- a/lcl/interfaces/gtk3/gtk3lclintf.inc
+++ b/lcl/interfaces/gtk3/gtk3lclintf.inc
@@ -693,6 +693,8 @@ begin
     Height := R.Bottom - R.Top;
   end;
 
+  WorkMask:=nil;
+
   if (Width = Image.Width) and (Height = Image.Height) then
   begin
     WorkImage := Image;
@@ -745,6 +747,7 @@ begin
       if InvertPixels then
         WorkMask.invertPixels(QImageInvertRGB);
         *)
+      if WorkMask.bits<>nil then
       Move(WorkMask.bits^, ARawImage.Mask^, ARawImage.MaskSize);
       // if InvertPixels then
       //  WorkMask.invertPixels(QImageInvertRGB);
diff --git a/lcl/interfaces/gtk3/gtk3widgets.pas b/lcl/interfaces/gtk3/gtk3widgets.pas
index b6e840ce66..50ff16f2c9 100644
--- a/lcl/interfaces/gtk3/gtk3widgets.pas
+++ b/lcl/interfaces/gtk3/gtk3widgets.pas
@@ -1712,11 +1712,14 @@ begin
   Result := False;
   FillChar(Msg, SizeOf(Msg), #0);
   if Event^.type_ = GDK_ENTER_NOTIFY then
-    Msg.Msg := LM_MOUSEENTER
+  begin
+    Msg.Msg := LM_MOUSEENTER;
+    NotifyApplicationUserInput(LCLObject, Msg.Msg);
+  end
   else
     Msg.Msg := LM_MOUSELEAVE;
 
-  NotifyApplicationUserInput(LCLObject, Msg.Msg);
+  //NotifyApplicationUserInput(LCLObject, Msg.Msg);
   Result := DeliverMessage(Msg, True) <> 0;
   {$IFDEF GTK3DEBUGCORE}
   MousePos.X := Round(Event^.crossing.x);
@@ -2838,6 +2841,12 @@ var
   Alloc: TGtkAllocation;
   AMinSize, ANaturalSize: gint;
 begin
+    if Self is TGtk3Button then
+    begin
+      dec(Awidth,4);
+      dec(Aheight,4);
+    end;
+
   ARect.x := ALeft;
   ARect.y := ATop;
   ARect.width := AWidth;
@@ -2855,6 +2864,9 @@ begin
     Widget^.get_preferred_width(@AMinSize, @ANaturalSize);
     Widget^.get_preferred_height(@AMinSize, @ANaturalSize);
 
+
+    Widget^.set_size_request(AWidth,AHeight);
+
     Widget^.size_allocate(@ARect);
     Widget^.set_allocation(@Alloc);
     if LCLObject.Parent <> nil then
@@ -3106,12 +3118,19 @@ var
 begin
   FHasPaint := True;
   FBorderStyle := bsNone;
+
   // wtLayout = using GtkLayout
   // FWidgetType := [wtWidget, wtLayout];
   // Result := TGtkLayout.new(nil, nil);
+
   FWidgetType := [wtWidget, wtContainer];
-  Result := TGtkFixed.new;
+  Result := TGtkFixed.new();
   Result^.set_has_window(True);
+  // as GtkFixed have no child control here - nobody triggers resizing
+  // GNOME takes care of it, but other WM - not
+  // this is here to make TGtk3Panel shown under Plasma
+  Result^.set_size_request(LCLObject.Width,LCLObject.Height);
+
   // AColor := Result^.style^.bg[0];
   // writeln('BG COLOR R=',AColor.red,' G=',AColor.green,' B=',AColor.blue);
   // now we make panel completely transparent.
@@ -3184,7 +3203,7 @@ begin
   fWidgetRGBA[0].Alpha:=0.7;
   PgtkFrame(Result)^.override_color(GTK_STATE_NORMAL,@Self.FWidgetRGBA[0]);}
   // nil resets color to gtk default
-  FWidget^.override_background_color(GTK_STATE_FLAG_NORMAL, nil);
+  //FWidget^.override_background_color(GTK_STATE_FLAG_NORMAL, nil);
 end;
 
 function TGtk3GroupBox.getText: String;
@@ -7085,7 +7104,7 @@ begin
   if not Assigned(LCLObject.Parent) then
   begin
     Result := TGtkWindow.new(GTK_WINDOW_TOPLEVEL);
-    Result^.set_size_request(0,0);
+    //Result^.set_size_request(0,0);
     gtk_widget_realize(Result);
     decor:=decoration_flags(AForm);
     gdk_window_set_decorations(Result^.window, decor);
diff --git a/lcl/interfaces/gtk3/gtk3winapi.inc b/lcl/interfaces/gtk3/gtk3winapi.inc
index 6bff6087e4..4923eded8d 100644
--- a/lcl/interfaces/gtk3/gtk3winapi.inc
+++ b/lcl/interfaces/gtk3/gtk3winapi.inc
@@ -3199,6 +3199,7 @@ begin
   Result := AWidget <> nil;
   if Result then
   begin
+    if AWidget.Widget = nil then exit;
     if AWidget.GetContainerWidget^.has_grab then
       gtk_grab_remove(AWidget.GetContainerWidget)
     else
@@ -3418,7 +3419,7 @@ begin
     if IsValidHandle(AHandle) then
     begin
       TGtk3Widget(AHandle).SetCapture;
-      if (Result <> 0) then
+      //if (Result <> 0) then
       begin
         Message.Msg := 0;
         FillChar(Message, SizeOf(Message), 0);