diff --git a/gst-libs/gst/app/gstappsink.h b/gst-libs/gst/app/gstappsink.h
index e7b91fdb36..040a4e1b43 100644
--- a/gst-libs/gst/app/gstappsink.h
+++ b/gst-libs/gst/app/gstappsink.h
@@ -42,6 +42,8 @@ typedef struct _GstAppSink GstAppSink;
 typedef struct _GstAppSinkClass GstAppSinkClass;
 typedef struct _GstAppSinkPrivate GstAppSinkPrivate;
 
+/* FIXME 2.0: Make the instance/class struct private */
+
 /**
  * GstAppSinkCallbacks: (skip)
  * @eos: Called when the end-of-stream has been reached. This callback
diff --git a/gst-libs/gst/app/gstappsrc.h b/gst-libs/gst/app/gstappsrc.h
index b7f6be849f..783b10cd9c 100644
--- a/gst-libs/gst/app/gstappsrc.h
+++ b/gst-libs/gst/app/gstappsrc.h
@@ -42,6 +42,8 @@ typedef struct _GstAppSrc GstAppSrc;
 typedef struct _GstAppSrcClass GstAppSrcClass;
 typedef struct _GstAppSrcPrivate GstAppSrcPrivate;
 
+/* FIXME 2.0: Make the instance/class struct private */
+
 /**
  * GstAppSrcCallbacks: (skip)
  * @need_data: Called when the appsrc needs more data. A buffer or EOS should be