diff --git a/matroska/KaxSemantic.h b/matroska/KaxSemantic.h
index 0ce79320..cb301cf4 100644
--- a/matroska/KaxSemantic.h
+++ b/matroska/KaxSemantic.h
@@ -312,6 +312,8 @@ DECLARE_MKX_UINTEGER_DEF(KaxCodecDecodeAll)
 };
 
 DECLARE_MKX_UINTEGER(KaxTrackOverlay)
+public:
+  libebml::filepos_t RenderData(libebml::IOCallback & output, bool bForceRender, ShouldWrite writeFilter) override;
 };
 
 DECLARE_MKX_UINTEGER_DEF(KaxCodecDelay)
@@ -970,7 +972,7 @@ typedef enum {
 
 /**
  *The Matrix Coefficients of the video used to derive luma and chroma values from red, green, and blue color primaries.
-For clarity, the value and meanings for MatrixCoefficients are adopted from Table 4 of ISO/IEC 23001-8:2016 or ITU-T H.273.
+For clarity, the value and meanings for MatrixCoefficients are adopted from Table 4 of ITU-H.273.
  */
 typedef enum {
   MATROSKA_VIDEO_MATRIXCOEFFICIENTS_IDENTITY         = 0,
@@ -1020,7 +1022,7 @@ typedef enum {
 
 /**
  *The transfer characteristics of the video. For clarity,
-the value and meanings for TransferCharacteristics are adopted from Table 3 of ISO/IEC 23091-4 or ITU-T H.273.
+the value and meanings for TransferCharacteristics are adopted from Table 3 of ITU-H.273.
  */
 typedef enum {
   MATROSKA_TRANSFER_RESERVED         = 0,
@@ -1046,7 +1048,7 @@ typedef enum {
 
 /**
  *The colour primaries of the video. For clarity,
-the value and meanings for Primaries are adopted from Table 2 of ISO/IEC 23091-4 or ITU-T H.273.
+the value and meanings for Primaries are adopted from Table 2 of ITU-H.273.
  */
 typedef enum {
   MATROSKA_VIDEO_PRIMARIES_RESERVED         = 0,
@@ -1109,7 +1111,7 @@ Values (big-endian) can be OR'ed.
  */
 typedef enum {
   MATROSKA_CONTENTENCODINGSCOPE_BLOCK            = 1, // All frame contents, excluding lacing data.
-  MATROSKA_CONTENTENCODINGSCOPE_PRIVATE          = 2, // The track's private data.
+  MATROSKA_CONTENTENCODINGSCOPE_PRIVATE          = 2, // The track's `CodecPrivate` data.
   MATROSKA_CONTENTENCODINGSCOPE_NEXT             = 4, // The next ContentEncoding (next `ContentEncodingOrder`. Either the data inside `ContentCompression` and/or `ContentEncryption`).
 } MatroskaContentEncodingScope;
 
@@ -1192,7 +1194,7 @@ typedef enum {
   MATROSKA_TARGET_TYPE_ALBUM            = 50, // The most common grouping level of music and video (equals to an episode for TV series).
   MATROSKA_TARGET_TYPE_PART             = 40, // When an album or episode has different logical parts.
   MATROSKA_TARGET_TYPE_TRACK            = 30, // The common parts of an album or movie.
-  MATROSKA_TARGET_TYPE_SUBTRACK         = 20, // Corresponds to parts of a track for audio (like a movement).
+  MATROSKA_TARGET_TYPE_SUBTRACK         = 20, // Corresponds to parts of a track for audio like a movement, or a scene in a movie.
   MATROSKA_TARGET_TYPE_SHOT             = 10, // The lowest hierarchy found in music or movies.
 } MatroskaTargetTypeValue;
 
diff --git a/src/KaxSemantic.cpp b/src/KaxSemantic.cpp
index a679f3fb..bd384f08 100644
--- a/src/KaxSemantic.cpp
+++ b/src/KaxSemantic.cpp
@@ -283,7 +283,7 @@ DEFINE_MKX_UNISTRING(KaxCodecSettings, 0x3A9697, 3, KaxTrackEntry, "CodecSetting
 DEFINE_MKX_STRING(KaxCodecInfoURL, 0x3B4040, 3, KaxTrackEntry, "CodecInfoURL", VERSION_DEPRECATED)
 DEFINE_MKX_STRING(KaxCodecDownloadURL, 0x26B240, 3, KaxTrackEntry, "CodecDownloadURL", VERSION_DEPRECATED)
 DEFINE_MKX_UINTEGER_DEF(KaxCodecDecodeAll, 0xAA, 1, KaxTrackEntry, "CodecDecodeAll", VERSION_DEPRECATED, 1)
-DEFINE_MKX_UINTEGER(KaxTrackOverlay, 0x6FAB, 2, KaxTrackEntry, "TrackOverlay", MatroskaProfile(false, false, 0))
+DEFINE_MKX_UINTEGER(KaxTrackOverlay, 0x6FAB, 2, KaxTrackEntry, "TrackOverlay", VERSION_DEPRECATED)
 DEFINE_MKX_UINTEGER_DEF(KaxCodecDelay, 0x56AA, 2, KaxTrackEntry, "CodecDelay", MatroskaProfile(true, false, 4), 0)
 DEFINE_MKX_UINTEGER_DEF(KaxSeekPreRoll, 0x56BB, 2, KaxTrackEntry, "SeekPreRoll", MatroskaProfile(true, false, 4), 0)
 
@@ -857,6 +857,11 @@ libebml::filepos_t KaxCodecDecodeAll::RenderData(libebml::IOCallback & /* output
   return 0;
 }
 
+libebml::filepos_t KaxTrackOverlay::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
+  assert(false); // no you are not allowed to use this element !
+  return 0;
+}
+
 libebml::filepos_t KaxOldStereoMode::RenderData(libebml::IOCallback & /* output */, bool /* bForceRender */, ShouldWrite /* writeFilter */) {
   assert(false); // no you are not allowed to use this element !
   return 0;