How can i check if a sequence is default or not

Hello, i need to know if a sequence is default or not

i’m trying to use this
eventBus.on(‘connection.changed’,250, oBuqsprhn.checkType);

but i dont know how to see if he changed for default or not, i was using the type of element to check this things, like bpmn:ParallelGateway, but for sequence the default and the normal type is the same.

EDIT 2:
i need to know how can i detect when i change the sequence type, like default to normal etc…
i tried to use connection.changed for this as well but this event is fire when a shape/connect is create by yours JS (bpmnio-moddler.js)

You can check wether or not a sequence flow is the default sequence flow of a flow element:

const businessObject = mySequenceFlow.businessObject, 
      source = mySequenceFlow.source,
      sourceBusinessObject = source.businessObject;

const isDefault = sourceBusinessObject.default &&
      sourceBusinessObject.default === businessObject;