old_contents: from frappe import _
  
  def get_data():
  	return {
  		'fieldname': 'sales_invoice',
  		'non_standard_fieldnames': {
  			'Delivery Note': 'against_sales_invoice',
  			'Journal Entry': 'reference_name',
  			'Payment Entry': 'reference_name',
  			'Payment Request': 'reference_name',
  			'Sales Invoice': 'return_against'
  		},
  		'internal_links': {
  			'Sales Order': ['items', 'sales_order'],
  			'Delivery Note': ['items', 'delivery_note']
  		},
  		'transactions': [
  			{
  				'label': _('Payment'),
  				'items': ['Payment Entry', 'Payment Request', 'Journal Entry']
  			},
  			{
  				'label': _('Reference'),
  				'items': ['Timesheet', 'Delivery Note', 'Sales Order']
  			},
  			{
  				'label': _('Returns'),
  				'items': ['Sales Invoice']
  			},
  		]
  	}
new_contents: from frappe import _
  
  def get_data():
  	return {
  		'fieldname': 'sales_invoice',
  		'non_standard_fieldnames': {
  			'Delivery Note': 'against_sales_invoice',
  			'Journal Entry': 'reference_name',
  			'Payment Entry': 'reference_name',
  			'Payment Request': 'reference_name',
  			'Sales Invoice': 'return_against'
  		},
  		'internal_links': {
  			'Sales Order': ['items', 'sales_order']
  		},
  		'transactions': [
  			{
  				'label': _('Payment'),
  				'items': ['Payment Entry', 'Payment Request', 'Journal Entry']
  			},
  			{
  				'label': _('Reference'),
  				'items': ['Timesheet', 'Delivery Note', 'Sales Order']
  			},
  			{
  				'label': _('Returns'),
  				'items': ['Sales Invoice']
  			},
  		]
  	}
subject: Revert sales invoice dn link issue