The plugin allows you to add code snippets to your WordPress installation. Therefore, there must be an input field that contains code snippets. Just look at what you have tried to implement there. You can also insert such code snippets directly via child-theme functions.php. So if you don’t have a child theme, it would also explain the need for such a plugin.

if it is a script like this:

function temporary_removal_title_tags(){
?>
<script>
  window.onload = function() {
    var elementsWithTitle = document.querySelectorAll('a, img, *[title]');
    for (var i = 0; i < elementsWithTitle.length; i++) {
        var element = elementsWithTitle[i];

        element.setAttribute("data-original-title", element.title);

        element.addEventListener("mouseenter", function() {
            this.title = ""; 
        });

        element.addEventListener("mouseleave", function() {
            this.title = this.getAttribute("data-original-title"); 
        });

        element.addEventListener("mousedown", function() {
            this.title = this.getAttribute("data-original-title");
        });
    }
  };
</script>
<?php
}
add_action('wp_footer', 'temporary_removal_title_tags');

then the mousedown (click) should bring the title back to the element. And lightbox had to show it.

the code snippet will work on your page for all images. Even on that graphics page.
But if you create these images in a different way – and i see some Enfold Lightbox on paintings page we had to find then a different solution.
But if you use the same way like on mixed media and graphics page – the code will work there too.

But as mentioned – it would be nice to have a fallback for the bottom-bar title on lightbox. my advise – and not only for seo purpose – give an alt tag to your images via media library.

and use that snippet with fallback alt -tag as title inside bottom-bar:

Edit
this checks if original image is present and if widget-text or alt is present :

function mixed_media_lightbox() {
?>
<script type="text/javascript">
window.addEventListener("DOMContentLoaded", function () { 
(function($){
    $('.widget_media_image').magnificPopup({
      delegate: 'img',
      type: 'image',
      removalDelay: 500,  // to allow animated closing in ms
      mainClass: 'avia-popup mfp-zoom-in mfp-image-loaded mixed-media',  
      midClick: true,
      gallery: { 
        enabled:true,
        preload: [1, 1] ,
      },
      image: {
        titleSrc: false,
        markup: '<div class="mfp-figure">'+
                  '<div class="mfp-close"></div>'+
                  '<div class="mfp-img"></div>'+
                    '<div class="mfp-bottom-bar">'+
                      '<div class="mfp-title"></div>'+
                  //  '<div class="mfp-counter"></div>'+
                    '</div>'+
                '</div>',
        },  
        callbacks: {
          elementParse: function(item) {
            var originalSrc = item.el.attr('src');
            var fullSizeSrc = originalSrc.replace(/-\d+x\d+\./, '.');

            // Create a temporary image object to check whether the full resolution exists
            var img = new Image();
            img.onload = function() {
              item.src = fullSizeSrc;
            };
            img.onerror = function() {
              item.src = originalSrc;
            };
            img.src = fullSizeSrc;
            item.src = originalSrc;
          },

          markupParse: function (template, values, item) {
            var title = ''; // Initialize title as an empty string. This is our default fallback.

            // 1. Highest Priority: Check for content from a nearby .widget_text element
            var textWidget = item.el.closest('.panel-grid-cell').find('.widget_text');
            if (textWidget.length && textWidget.html().trim() !== '') {
              title = textWidget.html();
            } else {
              // 2. Second Priority: If no text widget, check the image's alt attribute
              var altAttribute = item.el.attr('alt');
              if (altAttribute && altAttribute.trim() !== '') { // Checks if exists AND has non-empty content
                title = altAttribute;
              } else {
                // 3. Third Priority: If no alt, check the image's title attribute
                var titleAttribute = item.el.attr('title');
                if (titleAttribute && titleAttribute.trim() !== '') { // Checks if exists AND has non-empty content
                  title = titleAttribute;
                }
              }
            }

            // Finally, assign the title to values.title, wrapping it in <h3> ONLY if there's content
            if (title) {
              values.title = '<h3 class="heading">' + title + '</h3>';
            } else {
              values.title = ''; // If no title was found at all, ensure nothing is displayed
            }
          },
        },
    });
})(jQuery);
});
</script>
<?php
}
add_action('wp_footer', 'mixed_media_lightbox', 9999);

And

#top .mixed-media .mfp-image-holder .mfp-content {
  max-width: 1200px; 
  box-sizing: border-box; 
  padding-bottom: 90px; 
  vertical-align: middle; 
}

#top .mixed-media .mfp-bottom-bar {
  margin-top: -36px;
  position: absolute;
  top: 100%;
  left: 0;
  width: 100%;
  cursor: auto;
  background-color: rgba(0,0,0,0.3);
  backdrop-filter: blur(4px);
  padding: 5px 10px;
}

#top .mixed-media .mfp-bottom-bar .mfp-counter {
  right: 5px
}

#top .mixed-media .mfp-content img.mfp-img {
  width: auto;
  max-width: 100%;
  max-height: 90vh !important;
  height: auto;
  display: block;
  line-height: 0;
  box-sizing: border-box;
  padding: 40px 0 40px;
  margin: 0 auto;
}

#top .mixed-media .mfp-content .mfp-title .heading * {
  font-weight: 400 !important;
}

#top .mixed-media .mfp-content .mfp-title .heading p {
  margin: 0.3em 0;
}

#top .widget_media_image img {
  cursor: pointer;
}

Now – what you have to do. : not all your images do have that widget_text
See Paintings Page. Or you have tried to do it with enfold lightbox implementation there. ?

the script is working – but the shown title is not allways defined. the reason – see above.

Best would be to set an alt or title tag as fallback to all of your images. For SEO purpose it might be better to use the alt tag.
then you had to change the else condition to:

values.title = '<h3 class="heading">' + item.el.attr('alt') + '</h3>';

not familiar with site origin – but with the magnificPopup script ;)

but you can have your own lightbox script for those pages – using the magnificPopup :

Edit: see final solution at: https://kriesi.at/support/topic/lightbox-issues-2/#post-1486042

your img tags have no title nor alt attributes – but we can use the following description.

see here example with “burger” always visible – and with #footer-page as overlay.

https://basis.webers-testseite.de/

if you are interested in that – i gave you a step by step guide.

to get a “footer-page” with dynamically feed menues – you can use the menu shortcode :

function custom_named_menu_shortcode( $atts ) {
    extract( shortcode_atts( array(
        'name'  => '', // Default to an empty menu name
        'class' => 'custom-menu', // Default CSS class
        'depth' => 0, // Default depth (0 for unlimited)
        'title' => '', // New: Default to an empty title
        'title_tag' => 'h2', // New: Default title HTML tag
        'title_class' => 'menu-title', // New: Default title CSS class
    ), $atts ) );

    $output = ''; // Initialize output variable

    // If a title is provided, add it to the output
    if ( ! empty( $title ) ) {
        $output .= '<' . esc_attr( $title_tag ) . ' class="' . esc_attr( $title_class ) . '">' . esc_html( $title ) . '</' . esc_attr( $title_tag ) . '>';
    }

    if ( ! empty( $name ) ) {
        $output .= wp_nav_menu( array(
            'menu'            => $name,
            'menu_class'      => $class,
            'container'       => 'nav', // You can change this to 'div', false, etc.
            'container_class' => $class . '-container',
            'echo'            => false, // Important: returns the menu HTML instead of printing it
            'depth'           => $depth,
        ) );
    }
    return $output; // Return the accumulated output
}
add_shortcode( 'named_menu', 'custom_named_menu_shortcode' );

it is used like this:
[named_menu name="your-menu-name" class="my-custom-menu" depth="2" title="Our Main Menu"]

then you can setup your layout with codeblock elements – each of them represents a menu ( or different shortcode – f.e. social-media )

but for that i wouldn’t use the enfold burger icon – instead i would place a custom Button – perhaps a fixed button to toggle a class to hide/show this page.

if you like to bing those arrows to the center of the gallery height:

#top div .avia-gallery {
  position: relative;
}

.avia-gallery.av-slideshow-ui .avia-slideshow-arrows {
  width: 100%;
  height: 60px;
  top: calc(50% - 30px);
}

#top .avia-slideshow-arrows a {
  top: 0;
}

maybe put each of those elements in a separate 1/1 container. The icon-box and the gallery.

or try in quick css:

#top div .avia-gallery {
  position: relative;
}

on 6 items besides each other the setting vor less than 767px is allready set to 33% – and this looks nice to me.

Maybe you only like to influence the range inbetween:

@media only screen and (min-width: 768px) and (max-width: 989px) {
  #top .avia-custom-gallery .avia-gallery-thumb a {
    width: 25% !important;
  }
}

is it a gallery or a masonry gallery?

Rikard’s code should do the job – but the specificity is the same as the original rule. So you need to be more specific in your selector or override it with !important.

@media only screen and (max-width: 767px) {
   #top .avia-gallery .avia-gallery-thumb a {
     width: 50% !important;
   }
}

or

@media only screen and (max-width: 767px) {
  #top #wrap_all .avia-gallery .avia-gallery-thumb a {
    width: 50% ;
  }
}

if you do like to have it only on that gallery – use a custom class to that element.

Eventuell wird es dir auf dieser Seite deutlicher. https://webers-testseite.de/sticky-sidebar/

Das unmittelbare Elternelement zu dem Sticky Element ( bei Columns in einer Color-Section ist es der entry-content-wrapper ) muss der Flex-Container sein. Und auf deiner Seite muss gelten:

.responsive #top {
    overflow-x: visible;
}

 #top #wrap_all {
    overflow: visible;
}

Da es nur Sinn macht, wenn die Columns nebeneinander liegen, setzt man die Flex Bedingung am besten nur für diesen Fall ein; also für screens die größer sind als der Umbruchpunkt (768px oder 990px)

but you do not belong to the up and down of “Kia Ora!” section?

This comes from the slider above – that has 3 Groups and the last only got 4 items. So it’s height is less than the others.

Did it solve your problem, or did you find it to be less important than you thought?

I had understood him differently. For example, if he opens the page : Link via the menu, then it should open directly in the opened ajax style.

Versuch doch mal das in der child-theme functions.php:

function trigger_click_on_ajax_categories(){
?>
<script>
(function($){
    $(window).on('load', function(){
        // Prüfen, ob das Element mit der Klasse 'grid-links-ajax' auf der Seite existiert
        if ($('.grid-links-ajax').length > 0) {
            setTimeout(function() {
                // Sicherstellen, dass das erste Element vorhanden ist, bevor der Klick ausgelöst wird
                const firstGridItem = $(".grid-links-ajax .grid-entry.first");
                if (firstGridItem.length) {
                    firstGridItem.find('.grid-image').trigger('click');
                }
            }, 300);
        }
    });
})(jQuery);
</script>
<?php
}
add_action('wp_footer', 'trigger_click_on_ajax_categories');

eventuell musst du das timing etwas erhöhen.