Gravity Forms // Hooks // gform_userregistration_feed_settings_fields

gform_userregistration_feed_settings_fields.php

<?php

add_filter( 'gform_userregistration_feed_settings_fields', 'add_custom_user_registration_setting', 10, 2 );
function add_custom_user_registration_setting( $fields, $form ) {

	// adding my custom setting to the Additional Settings section
	$fields['additional_settings']['fields'][] = array(
		'name'      => 'myCustomSetting',
		'label'     => __( 'My Custom Setting', 'my-text-domain' ),
		'type'      => 'checkbox',
		'choices'   => array(
			array(
				'label'         => __( 'This is the checkbox label', 'my-text-domain' ),
				'value'         => 1,
				'name'          => 'myCustomSetting'
			)
		),
		'tooltip' => sprintf( '<h6>%s</h6> %s', __( 'Tooltip Header', 'my-text-domain' ), __( 'This is the tooltip description', 'my-text-domain' ) ),
		// this setting should only be visible for "create" feeds (and not "update" feeds)
		'dependency'  => array(
			'field'   => 'feedType',
			'values'  => 'create'
		)
	);

	return $fields;
}