What is the difference between the widget skins?
The Widget escalation method is different between the widget skins.
In the arcade skin, the escalation configurations are performed through the contact form, while in modern skin all the escalations are made from channeling rules.
In the modern widget, skin escalation configurations will be defined through channeling - learn how to define smart channeling.
To use the modern skin for channeling, all previous channel configurations should be removed.