Returning a ServiceNow List Field with Line Breaks Instead of Commas

if (current.getElement(fieldNames[i]).getED().getInternalType() == 'glide_list') {
	gs.info(getLineBreakedList(current,fieldNames[i]))
}

function getLineBreakedList(glideRecord,fieldName){
	var valuesStr = glideRecord.getValue(fieldName);
	var valuesArr = valuesStr.split(',');
	var listTable = glideRecord.getElement(fieldName).getED().reference;

	var listHtml = '';
	var glideRecRef = new GlideRecord(listTable);
	glideRecRef.addQuery('sys_id', 'IN',valuesStr);
	glideRecRef.query();
	while(glideRecRef.next()){
		listHtml += glideRecRef.getDisplayValue() + '<br/>'; //if you want a string field break replace '<br/>' with '\\n'
	}

	return listHtml;
}

If getElement is not working for you, you can create your own function, see this post