Hi Christian,
There are two options:
1. You can cancel the default action in onEventMove and create and add the event object manually using a deep copy of the data object:
dp.onEventMove = function(args) {
if (args.external) {
var cloned = JSON.parse(JSON.stringify(args.e.data));
dp.events.add(new DayPilot.Event(cloned));
args.preventDefault();
}
};
2. Or you can just make a copy of the tags object:
dp.onEventMove = function(args) {
if (args.external) {
args.e.data.tags = JSON.parse(JSON.stringify(args.e.data.tags));
}
};