This is an Enfold CSS that controls the respective element.
In this case it can be found here: /enfold/config-templatebuilder/avia-shortcodes/testimonials
But at least the Quick CSS variant will remain intact when you update Enfold.

Perhaps the developers should set this setting to this value (“Block and Hide reset all options button”) by default after Enfold Activation. Too many people have accidentally pressed this button despite a warning pop-up.

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…

or – if you only miss those icons – you can find them in the docu as downloadable zip files : https://kriesi.at/documentation/enfold/icon/#download-fontello-or-flaticon-icons-included-in-enfold-demos

for medical : https://kriesi.at/documentation/enfold/wp-content/uploads/sites/22/2022/08/medical.zip

Edit: here is the solution with working separators on those color-sections

the color-section that should react like this:
give a custom class to it: av-video-section
give a background-color to it that does not disturb your video switch (not white – something that fits to your video content
place a codeblock element on top of your color-section ( codeblock to content – not as codesnippet)

<video class="responsive-background-video" 
        autoplay muted loop playsinline
        data-video-mobile="path/to/mobile.mp4"
        data-video-desktop="path/to/desktop.mp4">
    <source src="" type="video/mp4">
</video>

this to your quick css:

.responsive #top #wrap_all .avia-section.av-video-section {
  position: relative;
  overflow: hidden; 
  min-height: initial; /* taken from Enfold section setting  */
}
.responsive #top #wrap_all .avia-section.av-video-section .container {
  position: relative;
  z-index: 1;
  max-width: 100% !important;
  width: 100% !important;
  padding: 0 !important;
}  
.responsive #top #wrap_all .avia-section.av-video-section .responsive-background-video {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover !important;
  z-index: 0;
  min-height: inherit; /* transfer from Enfold section setting  */
}
.responsive #top #wrap_all .avia-section.av-video-section .avia-divider-svg {
  z-index:2;
}
.responsive #top #wrap_all .avia-section.av-video-section .avia-divider-svg.avia-to-front {
  z-index:100;
}

the snippet for child-theme functions.php

function custom_responsive_background_video_script() {
?>
<script>
(function($) {
    "use strict";

    $(document).ready(function() {
        $('.responsive-background-video').each(function() {
            const video = this;
            const $video = $(video);
            const source = video.querySelector('source');
            const win = $(window);
            
            // Get video paths from data attributes
            const mobileVideo = $video.data('video-mobile');
            const desktopVideo = $video.data('video-desktop');
            
            if (!mobileVideo || !desktopVideo) return;
            
            function updateVideoSource() {
                const isMobile = win.width() < 768;
                const newSrc = isMobile ? mobileVideo : desktopVideo;
                
                if (source.src.indexOf(newSrc) === -1) {
                    source.src = newSrc;
                    video.load();
                }
            }
            
            // Initial load
            updateVideoSource();
            
            // Resize handling
            win.on('debouncedresize', updateVideoSource);
        });
    });
})(jQuery);
</script>
<?php
}
add_action('wp_footer', 'custom_responsive_background_video_script', 999);

see example page with divider : https://webers-testseite.de/background-video/

what you can do – ( not with enfold specific tools )!

do not set the background-image with enfold color-section settings.
put into the color-section on top a code-block element with this content
(adjust to your path and videos):

See Solution on next posts

you do not see the image above in https://kriesi.at/support/topic/how-to-remove-the-bar-above-the-main-menu-preferebly-without-any-css-code/#post-1490697
click on it to enlarge the image.

so Enfold (or Enfold-Child) – Header then on the right “extra Elements” Tab
remove all entries there.

Header Social Icons : No social Icons
Header Secondary Menu : No Secondary Menu
Header Phone Number/Extra Info: No Phone Number/Extra Info