Multiple instances of same GF form on the same page

functions.php

<?php
/**
 * Multiple instances of same GF form on the same page
 */
add_filter( 'gform_get_form_filter_1', 'gform_get_form_filter_handler', 10, 2 );
add_filter( 'gform_confirmation_1', 'gform_get_form_filter', 10, 2 );
function gform_get_form_filter_handler( $form_string, $form ){
	// if form has been submitted, use the submitted ID, otherwise generate a new unique ID
	if ( isset( $_POST['gform_random_id'] ) ) {
		$random_id = absint( $_POST['gform_random_id'] ); // Input var okay.
	} else {
		$random_id = mt_rand();
	}

	// this is where we keep our unique ID
	$hidden_field = "<input type='hidden' name='gform_field_values'";

	// define all occurences of the original form ID that wont hurt the form input
	$strings = array(
		' gform_wrapper'                                                   => ' gform_wrapper gform_wrapper_original_id_' . $form['id'],
		"for='choice_"                                                      => "for='choice_" . $random_id . '_',
		"id='label_"                                                        => "id='label_" . $random_id . '_',
		"'gform_wrapper_" . $form['id'] . "'"                               => "'gform_wrapper_" . $random_id . "'",
		"'gf_" . $form['id'] . "'"                                          => "'gf_" . $random_id . "'",
		"'gform_" . $form['id'] . "'"                                       => "'gform_" . $random_id . "'",
		"'gform_ajax_frame_" . $form['id'] . "'"                            => "'gform_ajax_frame_" . $random_id . "'",
		'#gf_' . $form['id'] . "'"                                          => '#gf_' . $random_id . "'",
		"'gform_fields_" . $form['id'] . "'"                                => "'gform_fields_" . $random_id . "'",
		"id='field_" . $form['id'] . '_'                                    => "id='field_" . $random_id . '_',
		"for='input_" . $form['id'] . '_'                                   => "for='input_" . $random_id . '_',
		"id='input_" . $form['id'] . '_'                                    => "id='input_" . $random_id . '_',
		"id='choice_" . $form['id'] . '_'                                   => "id='choice_" . $random_id . '_',
		"'gform_submit_button_" . $form['id'] . "'"                         => "'gform_submit_button_" . $random_id . "'",
		'"gf_submitting_' . $form['id'] . '"'                               => '"gf_submitting_' . $random_id . '"',
		"'gf_submitting_" . $form['id'] . "'"                               => "'gf_submitting_" . $random_id . "'",
		'#gform_ajax_frame_' . $form['id']                                  => '#gform_ajax_frame_' . $random_id,
		'#gform_wrapper_' . $form['id']                                     => '#gform_wrapper_' . $random_id,
		'#gform_' . $form['id']                                             => '#gform_' . $random_id,
		"trigger('gform_post_render', [" . $form['id']                      => "trigger('gform_post_render', [" . $random_id,
		'gformInitSpinner( ' . $form['id'] . ','                            => 'gformInitSpinner( ' . $random_id . ',',
		"trigger('gform_page_loaded', [" . $form['id']                      => "trigger('gform_page_loaded', [" . $random_id,
		"'gform_confirmation_loaded', [" . $form['id'] . ']'                => "'gform_confirmation_loaded', [" . $random_id . ']',
		'gf_apply_rules(' . $form['id'] . ','                               => 'gf_apply_rules(' . $random_id . ',',
		'gform_confirmation_wrapper_' . $form['id']                         => 'gform_confirmation_wrapper_' . $random_id,
		'gforms_confirmation_message_' . $form['id']                        => 'gforms_confirmation_message_' . $random_id,
		'gform_confirmation_message_' . $form['id']                         => 'gform_confirmation_message_' . $random_id,
		'if(formId == ' . $form['id'] . ')'                                 => 'if(formId == ' . $random_id . ')',
		"window['gf_form_conditional_logic'][" . $form['id'] . ']'          => "window['gf_form_conditional_logic'][" . $random_id . ']',
		"trigger('gform_post_conditional_logic', [" . $form['id'] . ','     => "trigger('gform_post_conditional_logic', [" . $random_id . ',',
		'gformShowPasswordStrength("input_' . $form['id'] . '_'             => 'gformShowPasswordStrength("input_' . $random_id . '_',
		"gformInitChosenFields('#input_" . $form['id'] . '_'                => "gformInitChosenFields('#input_" . $random_id . '_',
		"jQuery('#input_" . $form['id'] . '_'                               => "jQuery('#input_" . $random_id . '_',
		'gforms_calendar_icon_input_' . $form['id'] . '_'                   => 'gforms_calendar_icon_input_' . $random_id . '_',
		"id='ginput_base_price_" . $form['id'] . '_'                        => "id='ginput_base_price_" . $random_id . '_',
		"id='ginput_quantity_" . $form['id'] . '_'                          => "id='ginput_quantity_" . $random_id . '_',
		'gfield_price_' . $form['id'] . '_'                                 => 'gfield_price_' . $random_id . '_',
		'gfield_quantity_' . $form['id'] . '_'                              => 'gfield_quantity_' . $random_id . '_',
		'gfield_product_' . $form['id'] . '_'                               => 'gfield_product_' . $random_id . '_',
		'ginput_total_' . $form['id']                                       => 'ginput_total_' . $random_id,
		'GFCalc(' . $form['id'] . ','                                       => 'GFCalc(' . $random_id . ',',
		'gf_global["number_formats"][' . $form['id'] . ']'                  => 'gf_global["number_formats"][' . $random_id . ']',
		'gform_next_button_' . $form['id'] . '_'                            => 'gform_next_button_' . $random_id . '_',
		$hidden_field                                                       => "<input type='hidden' name='gform_random_id' value='" . $random_id . "' />" . $hidden_field,
	);

	// allow addons & plugins to add additional find & replace strings
	$strings = apply_filters( 'gform_multiple_instances_strings', $strings, $form['id'], $random_id );

	// replace all occurences with the new unique ID
	foreach ( $strings as $find => $replace ) {
		$form_string = str_replace( $find, $replace, $form_string );
	}

	return $form_string;
}