MP3Tag Title not used as MKV Titles

[Florian]

@RobertM

The DIRECTOR, GENRE, and other tags that get created by default at level 30 by Mp3tag would all really be better if they were created at level 50 for MKV files.

I've just released Mp3tag v3.28e, which changes the default mapping to T=50 for MKV Matroska video files.