diff --git a/lcl/interfaces/gtk/gtkproc.inc b/lcl/interfaces/gtk/gtkproc.inc
index b249cab384..07379eef25 100644
--- a/lcl/interfaces/gtk/gtkproc.inc
+++ b/lcl/interfaces/gtk/gtkproc.inc
@@ -12,7 +12,7 @@
  *                                                                           *
  *  This file is part of the Lazarus Component Library (LCL)                 *
  *                                                                           *
- *  See the file COPYING.modifiedLGPL.txt, included in this distribution,        *
+ *  See the file COPYING.modifiedLGPL.txt, included in this distribution,    *
  *  for details about the copyright.                                         *
  *                                                                           *
  *  This program is distributed in the hope that it will be useful,          *
@@ -5526,81 +5526,6 @@ begin
   FreeMem(ImgData);
 end;
 
-{
-  function GdkPixbufAddBitmapMask
-
-  pixbuf - original pixbuf to mask
-  mask - mask bitmap
-  mask_value - bit value that should be masked
-
-  Returns new pixbuf with applied mask
-}
-function GdkPixbufAddBitmapMask(pixbuf: PGdkPixbuf; mask: PGdkBitmap; mask_value: byte): PGdkPixbuf;
-var
-  i, j, w, h, r, n: integer;
-  src, dest: Pguchar;
-  Image: PGdkImage;
-  s_buf, d_buf: PCardinal;
-begin
-  Result := nil;
-
-  // first check for null images
-  if (pixbuf = nil) or (mask = nil) then
-    exit;
-
-  n := gdk_pixbuf_get_n_channels(pixbuf);
-  gdk_drawable_get_size(mask, @w, @h);
-
-  // second check. we cannot process pixbuf with channels <> 4
-  // or with different size that image
-  if (n <> 4) or (w <> gdk_pixbuf_get_width(pixbuf)) or
-     (h <> gdk_pixbuf_get_height(pixbuf)) then
-    exit;
-
-  r := gdk_pixbuf_get_rowstride(pixbuf);
-
-  // we need Image to read pixels
-  Image := gdk_drawable_get_image(mask, 0, 0, w, h);
-
-  // source pixels of pixbuf
-  src := gdk_pixbuf_get_pixels(pixbuf);
-
-  // allocate destination buffer for new pixbuf
-  dest := g_malloc(4 * r * h);
-
-  // to run on buffer we need one more pointer to it
-  d_buf := PCardinal(dest);
-
-  for i := 0 to h - 1 do
-  begin
-    // buffer of source row
-    s_buf := PCardinal(src + i * r);
-    for j := 0 to w - 1 do
-    begin
-      if gdk_image_get_pixel(Image, j, i) = mask_value then
-      begin
-        // if pixel should be masked we fill color with zeros
-        d_buf^ := 0;
-      end else
-      begin
-        // in other case we copy it from source
-        d_buf^ := s_buf^;
-      end;
-      inc(d_buf);
-      inc(s_buf);
-    end;
-  end;
-  // image is no more needed, so can be disposed
-  gdk_image_unref(Image);
-
-  // craete result pixbuf from destination buffer
-  Result := gdk_pixbuf_new_from_data(dest, GDK_COLORSPACE_RGB, true, 8, w, h, r, nil, nil);
-
-  // if pixbuf is not created, then destination data should be freed
-  if Result = nil then
-    g_free(dest);
-end;
-
 {-------------------------------------------------------------------------------
   method CreatePixbufFromDrawable
   Params: ASource: The source drawable
diff --git a/lcl/interfaces/gtk/gtkproc.pp b/lcl/interfaces/gtk/gtkproc.pp
index f49918056f..e7d24f89f8 100644
--- a/lcl/interfaces/gtk/gtkproc.pp
+++ b/lcl/interfaces/gtk/gtkproc.pp
@@ -13,7 +13,7 @@
  *                                                                           *
  *  This file is part of the Lazarus Component Library (LCL)                 *
  *                                                                           *
- *  See the file COPYING.modifiedLGPL.txt, included in this distribution,        *
+ *  See the file COPYING.modifiedLGPL.txt, included in this distribution,    *
  *  for details about the copyright.                                         *
  *                                                                           *
  *  This program is distributed in the hope that it will be useful,          *
@@ -609,9 +609,7 @@ procedure LoadPixbufFromLazResource(const ResourceName: string;
   var Pixbuf: PGdkPixbuf);
 procedure LoadXPMFromLazResource(const ResourceName: string;
   Window: PGdkWindow; var PixmapImg, PixmapMask: PGdkPixmap);
-function GdkPixbufAddBitmapMask(pixbuf: PGdkPixbuf; mask:
-  PGdkBitmap; mask_value: byte): PGdkPixbuf;
-  
+
 function CreatePixbufFromDrawable(ASource: PGdkDrawable; AColorMap:PGdkColormap; AIncludeAplha: Boolean; ASrcX, ASrcY, ADstX, ADstY, AWidth, AHeight :longint): PGdkPixbuf;
 
 
diff --git a/lcl/interfaces/gtk/gtkwinapi.inc b/lcl/interfaces/gtk/gtkwinapi.inc
index d3bf238d08..6c9e5ca5a9 100644
--- a/lcl/interfaces/gtk/gtkwinapi.inc
+++ b/lcl/interfaces/gtk/gtkwinapi.inc
@@ -2482,11 +2482,23 @@ begin
           {$IFDEF DebugGDKTraps}
           BeginGDKErrorTrap;
           {$ENDIF}
-          if GDIBitmapObject <> nil then
-            gdk_bitmap_unref(GDIBitmapObject);
-          If (Visual <> nil) and (not SystemVisual) then
+          case GDIBitmapType of
+            gbBitmap:
+              begin
+                if GDIBitmapObject <> nil then
+                  gdk_bitmap_unref(GDIBitmapObject);
+              end;
+            gbPixmap:
+              begin
+                if GDIPixmapObject.Image <> nil then
+                  gdk_pixmap_unref(GDIPixmapObject.Image);
+                if GDIPixmapObject.Mask <> nil then
+                  gdk_bitmap_unref(GDIPixmapObject.Mask);
+              end;
+          end;
+          if (Visual <> nil) and (not SystemVisual) then
             gdk_visual_unref(Visual);
-          If Colormap <> nil then
+          if Colormap <> nil then
             gdk_colormap_unref(Colormap);
           {$IFDEF DebugGDKTraps}
           EndGDKErrorTrap;