Track names cause merging to break

[xp2-882030kgz010602]

I don't know what's going on here.

var track1=new MidiWriter.Track();
track1.addEvent(new MidiWriter.NoteEvent({pitch:["A3"],duration:'4'}));
var track2=new MidiWriter.Track();
//Uncommenting the below line causes the tracks to be merged incorrectly
//track2.addTrackName("name");
track2.addEvent(new MidiWriter.NoteEvent({pitch:["A3"],duration:'4',wait:'T256'}));
track1.mergeTrack(track2);