I’m not sure if I can post stuff like this on forum, but could git repo host switch int MidiMessageSequence::getIndexOf (MidiEventHolder* const event) to int MidiMessageSequence::getIndexOf (const MidiEventHolder* const event)?
Looks like OwnedArray::indexOf() accept const parameter as well, so that should not be a problem.
I don’t feel experienced enough to make pull request, since I’m not sure it won’t drag anything behind it.