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function newRecord(event) {
	_super.newRecord(event)
	city = 'Amersfoort'
	return
}

other options

_super keyword

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Limitations

There are no many limitations to form inheritance. If you have a element on the super form you can not 

: Can only edit some types of properties inherited from a super form, not all. Can't alter any properties of elements or parts. Cannot insert new parts inbetween existing, only after existing parts

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