parseerror in forms when migrating site

Sorry I can’t share the link to the site yet. Was trying to submit a ticket to Elementor, but the page is just hanging (on three different browsers). So I am posting here for the community’s help.

I am having a hard time debugging a problem with pop-up windows that are being used for redirection. I have a site in UAT https://uat2.xyz.com (the XYZ is a placeholder), that is built in WordPress and Elementor PRO on IIS and PHP 8. The site is on an EC2 machine behind an AWS ALB and Imperva (a cloud Firewall).

The problem I am facing is with pop-ups and redirection. I have several pop-ups in the site that perform redirection to other sites (being used as speedbumps). Since I need to open the links in new tabs, I have been forced to use the following example script that I obtained from help forums:

<script>
    jQuery( document ).ready(function( $ ){
    $( '#leaving-ymcacambridge-form' ).on('submit_success', function(){
        // form has been submitted
        window.open('https://cambridgeymca.org/', '_blank');
    });
});
</script>

This window contains a form with just one button labelled “I Accept”. I attached a “Popup” action to the button with the “Close Popup” directive. The script is placed in an html widget in the popup window (and not inside the form). I ensured that the only form field is hidden and has a unique ID as recommended by Elementor.

The popup windows work as long as I am on the original site http://uat2.xyz.com.

Then I migrate to https://www.xyz.com and follow all the migration steps (i.e. edit the bindings in IIS to http://www.xyz.com, use the Replace URLS tool in Elementor, Regenerate the CSS files, change the SITE URL and HOME URL entries in wp-config.php etc.). I am still on the same EC2 instance and connected to the same AWS ALB and still behind the Imperva firewall.

The pop-ups seem to work for a few minutes. After that they start failing – the popup window becomes taller and a message is printed on the window in invisible text. I cut and pasted the text and it says “parse error”. Inspecting the element shows an elementor-danger-message class appearing. The problem appears on all desktop and mobile browsers.

I moved back the site to https://uat2.xyz.com and everything works fine again!!

This problem has delayed our go-live by two weeks! All help from the experts will be highly appreciated.

The page I need help with: [log in to see the link]