diff --git a/libavformat/matroska.h b/libavformat/matroska.h
index 86968a8de1..9e33e51c94 100644
--- a/libavformat/matroska.h
+++ b/libavformat/matroska.h
@@ -271,6 +271,7 @@ typedef enum {
   MATROSKA_TRACK_TYPE_COMPLEX  = 0x3,
   MATROSKA_TRACK_TYPE_LOGO     = 0x10,
   MATROSKA_TRACK_TYPE_SUBTITLE = 0x11,
+  MATROSKA_TRACK_TYPE_BUTTONS  = 0x12,
   MATROSKA_TRACK_TYPE_CONTROL  = 0x20,
   MATROSKA_TRACK_TYPE_METADATA = 0x21,
 } MatroskaTrackType;