diff --git a/demos/gtk-demo/application.gresource.xml b/demos/gtk-demo/application.gresource.xml
index ed5c81e9ad..485053532e 100644
--- a/demos/gtk-demo/application.gresource.xml
+++ b/demos/gtk-demo/application.gresource.xml
@@ -1,11 +1,11 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <gresources>
   <gresource prefix="/logos">
-    <file>gtk-logo-24.png</file>
-    <file>gtk-logo-48.png</file>
+    <file preprocess="to-pixdata">gtk-logo-24.png</file>
+    <file preprocess="to-pixdata">gtk-logo-48.png</file>
   </gresource>
   <gresource prefix="/ui">
-    <file>application.ui</file>
-    <file>menus.ui</file>
+    <file preprocess="xml-stripblanks">application.ui</file>
+    <file preprocess="xml-stripblanks">menus.ui</file>
   </gresource>
 </gresources>