This allows your gravity forms to load via ajax to ensure they work correctly with page transitions that have no window/document.onload

functions.php

<?php

  // ***IMPORTANT*** PLACE THIS PART IN YOUR ENQUEUE SCRIPTS FUNCTION AFTER YOUR SCRIPTS.JS ENQUEUE
  wp_localize_script( 'change-me-to-your-script-file-handle', 'ajax', array(
		'url' => admin_url( 'admin-ajax.php' )
	));
	// You can now use ajax.url as the URL in your ajax calls
	
  // PLACE THIS ANYWHERE IN YOUR FUNCTIONS.PHP FILE
  
  // Add the action and nopriv action to account for users not logged in
  add_action( 'wp_ajax_nopriv_load_gravity_form', 'load_gravity_form' );
  add_action( 'wp_ajax_load_gravity_form', 'load_gravity_form' );
  
  function load_gravity_form() {
    
    // These return the following:
    // The form ID
    $gfId = intval($_GET['formid']); 
    // Rather or not to add the form title - converted to a boolean
    $gfTitle = filter_var($_GET['formtitle'], FILTER_VALIDATE_BOOLEAN);
    // Rather or not to add the form description - converted to a boolean
    $gfDesc = filter_var($_GET['formdescr'], FILTER_VALIDATE_BOOLEAN);
    // Rather or not to the form should be submitted via ajax - converted to a boolean
    $gfAjax = filter_var($_GET['formajax'], FILTER_VALIDATE_BOOLEAN);
    
    // This is the shortcode to embed the form
    gravity_form($gfId, $gfTitle, $gfDesc, false, '', $gfAjax, 1);
    
    die();
    
  }

?>

GRAVITY FORMS WITH SWUP - BARBA PAGE TRANSITIONS

This allows your gravity forms to load via ajax to ensure they work correctly with page transitions that have no window/document.onload

header.php

<?php
  // This function will enqueue the necessary styles and scripts for the 
  // specified Gravity Form. This is useful when manually embedding a form 
  // outside the WordPress loop using the function call.
  //
  // This is placed in a foreach loop to account for all forms including 
  // future forms you may not have an ID for yet. If you only have a couple 
  // forms and know the Ids won't change you can just add them as such:
  // gravity_form_enqueue_scripts( 1, true );
  //
  // Place this right before wp_head();
	$forms = GFAPI::get_forms();

	foreach ($forms as $form) {
		gravity_form_enqueue_scripts( $form['id'], true );
	}
	
?>

page-template.php

<div class= "form-wrap">
    
  <!-- I am using Gravity forms ACF field to allow user to select which form they wish to display. 
  You can download and find more at https://github.com/DannyvanHolten/acf-gravityforms-add-on -->
  <?php $acf_field_form_id = get_sub_field( 'field_name_for_form' ); ?>
  
  <!-- Set the form ID to match user selection, set whether the form should show 
  title and/or descrition, and rather it should be submitted via ajax or not --> 
  <div class="gfid" data-id="<?php echo $acf_field_form_id; ?>" data-title="true" data-descr="true" data-ajax="true"></div>

</div>

scripts.js

// Grab all items from your page template file
var yourForm = $('.form-wrap'),
    gfItem = yourForm.find('.gfid'),
    gfNum = gfItem.attr('data-id'),
    gfId = parseInt(gfNum),
    gfTitle = gfItem.attr('data-title'),
    gfDesc = gfItem.attr('data-descr'),
    gfAjax = gfItem.attr('data-ajax');

if (yourForm.length) {
  
  $.ajax({
    type: "GET",
    // Make sure this matches what you set in your wp_enqueue_script
    url: ajax.url,
    data: {
      // The name of the function declared in functions.php
      action: 'load_gravity_form',
      // The data pulled from page-template.php
      formid: gfId,
      formtitle: gfTitle,
      formdescr: gfDesc,
      formajax: gfAjax,
    }
  }).done(function (data) {
    yourForm.html(data);
  });

}

Wow, thanks for all these snippets! Did you manage to make it work with a recaptcha in the form?

@atoupet-toki with the updated version of the Gravity Forms reCAPTCHA Add-On, reCAPTCHA scripts are now automatically enqueued.

BTW, if you're interested, I've created an "updated" version of this script with functional conditional logic : https://gist.github.com/Striffly/fa79b85901dd6c98a8075a35d7dc45ee