I edited this year's trombone forum video. Thanks, to everyone who participated.
Fun fact: the melody to "In Dulci Jubilo" is so ancient that no one knows who composed it.
But if you use it in a YouTube video you get a copyright warning on behalf of "Wise Music Group" and "LatinAutorPerf," who somehow claim to own the rights to the melody.
Not some new arrangement of the music... they claim to own the melody itself... the 600 year-old public domain melody.