diff --git a/src/x11/meta-x11-selection-output-stream.c b/src/x11/meta-x11-selection-output-stream.c
index cd7b83a15..9e8d3eb52 100644
--- a/src/x11/meta-x11-selection-output-stream.c
+++ b/src/x11/meta-x11-selection-output-stream.c
@@ -114,7 +114,7 @@ get_max_request_size (MetaX11Display *display)
   if (size <= 0)
     size = XMaxRequestSize (display->xdisplay);
 
-  return size - 100;
+  return (size - 100) * 4;
 }
 
 static gboolean