Are you talking about the tooltips displayed by the browser itself when hovering over the image?
They appear automatically if the image has a title attribute.

However, if you have a gallery that displays images in a lightbox, this title attribute is also displayed as text in the bottom bar of the lightbox. Completely removing the title tag would therefore be suboptimal. For galleries, you can switch to displaying the description or caption instead, but this is not possible for all Enfold elements.
So if it only affects the galleries on your site, you could do that, but you would then have to update the description of the images, for example.

There is a snippet that, when placed in the child theme’s functions.php, temporarily removes this title tag on hover but adds it back when clicked:

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');

here you see that this script is working for all anchor elements or images – or all elements that have a title-tag

Filesize is on original jpg small enough – so you can insert the full image. Maybe that is a bit sharper then.

And maybe you switch earlier to hamburger menu :

@media only screen and (max-width: 1200px) {
    #top #header .av-main-nav > li.menu-item  {
        display: none!important;
    }
    #top #header .av-burger-menu-main {
        cursor: pointer;
        display: block!important;
    }
}

Open that image link in your browser: https://dapoostkapelle.nl/wp-content/uploads/2025/06/First_business_card_5.png

you then can see the whitespace around it.

Would you like to hide only the logo image or both the logo image and navigation?
Would you like to hide it on small screen sizes or exclusively on mobile devices?

now – thanks for the admin permissions.

i did what i mentioned above: for the thumbs in grid i take the portfolio size (495×400)
using that snippet to have original images in the ajax preview image ( on imagify you have choosen to have no compression – so original image might be of less file-size than the recalculated large image-size )
and disabeling the enfold option to use lazyloading ( maybe the option of wp-rocket is better )

but with these changings – you can see a much better loading performance.

in additon – i decided to show on lightbox the full image ( because your large recalculated images are much bigger in file-size than the full one )
and to have no scroll on background – on opend lightbox.

ok – this seems to be enough inside child-theme functions.php:

add_filter("avf_ajax_preview_image_size", function($size) {
   $size = "full";
   return $size;
}, 10, 1);

PS : you should use for the thumbnails in the grid recalculated smaller images e.g.

you are now using the full image (no-scaling).

Edited – because there is that existing filter to influence the shown image in preview …

can we influence the image shown in the ajax preview ( that img insided avia-gallery-big ) – it seems to use the recalculated “large” image.
But as you know this might be bigger in file size than the original uploaded image!
I can not find a filter to adjust it.

or could we influence it by
$params['preview_size'] = apply_filters( 'avf_ajax_preview_image_size', 'gallery' );

i can find this in portfolio.php

//	create array with responsive info for lightbox
	$img = Av_Responsive_Images()->responsive_image_src( $attachment->ID, 'large' );

bring it to full will often reduce file-size – as you know that Enfold standard compression leads to bigger file-sizes on large image.

ok – i found the place to change in gallery.php (line 757)
$prev = wp_get_attachment_image_src( $attachment->ID, $preview_size );

if we would use :
$prev = wp_get_attachment_image_src( $attachment->ID, 'full' );

looking to his page f.e.:
the krebs-treppen-systeme-gelaender-system30-3.jpg is 121kb
but krebs-treppen-systeme-gelaender-system30-3-1030×839.jpg is 268kb

the whole page got over 112MB images – and could be reduced to a half size.

you can try:

#top .avia-featureimage-slideshow .avia-caption-title a {
  display: inline-block;
  line-height: 1.4em;
  background-color: rgba(0,0,0,0.3);
  backdrop-filter: blur(4px);
  padding: 5px 8px;
  border: 2px solid #FFF;
  border-radius: 5px
}

Just leave out the border styling if you don’t like to have it. I’ve now adjusted it so that it fits the button.

have you followed my link to the testpage? There is the video in the “background!” you can see the layout of that in the placed image below.
The rest is the css you need.
PS: Hope Mike could help you – because as a participant i can not see private content area.

see my edit above – posting the same time

try:

#top picture.avia_image {
  display: flex !important;
}

and maybe you like to have more contrast on hovering the images:

#top a.avia_image .av-image-caption-overlay-center {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  display:  grid;
  margin: 5px 25px;
  font-size: 1.2em
}

#top a.avia_image:hover .av-image-caption-overlay-center {
  color: #940000;
  background-color: rgba(255,255,255,0.6);
  backdrop-filter: blur(4px);
}

#top .av-image-caption-overlay-center p {
  margin: 10px 0 !important;
}

Where can we inspect that issue?
– ok i found your page tabijapon –
do you have a webp plugin installed? if i place an image element with enfold only and set the animation to “slightly zoom the image” – i do not have these bars.
Now i try to find out where it comes from…