diff --git a/docs/changes.txt b/docs/changes.txt
index 9c5f4a68e8..a31a055995 100644
--- a/docs/changes.txt
+++ b/docs/changes.txt
@@ -593,7 +593,8 @@ All (GUI):
 wxGTK:
 
 - Fix mouse wheel scrolling in wxListCtrl broken just before 3.0.0.
-- Fix memory leak in wxSocket
+- Fix memory leak in wxSocket.
+- Fix raw access to wxBitmap pixels after drawing on it using wxMemoryDC.
 
 wxMSW:
 
diff --git a/src/gtk/bitmap.cpp b/src/gtk/bitmap.cpp
index 6ab6bcb628..f81e7104a8 100644
--- a/src/gtk/bitmap.cpp
+++ b/src/gtk/bitmap.cpp
@@ -1428,6 +1428,11 @@ void *wxBitmap::GetRawData(wxPixelDataBase& data, int bpp)
     }
 #else
     GdkPixbuf *pixbuf = GetPixbuf();
+
+    // Pixmap will get out of date when our pixbuf is accessed directly, so
+    // ensure we don't keep the old data in it.
+    PurgeOtherRepresentations(Pixbuf);
+
     const bool hasAlpha = HasAlpha();
 
     // allow access if bpp is valid and matches existence of alpha