Currently it is possible to use all features for the same domain also on a sub domain by settings document.domain in the parent and the iframe page.
You can read the description how this is configured on the “External workaround” tab.
Chrome will disable modifying `document.domain` to relax the same-origin policy in version 109 right now.
You can see the details here: https://developer.chrome.com/blog/immutable-document-domain/
Solution
1. Use ai_external.js
So currently I recommend to switch to the normal external workaround where you have to include the ai_external.js to the page in the iframe. In the free version then still the auto height is supported. In the pro version you will get even more features like shown here.
2. Use the “Origin-Agent-Cluster” header
If you still want to use document.domain you need to send the header like described in the blog of chrome.
2 options do do this are:
1. Setting the header in php
Add the following line to all pages in the iframe before any HTML is returned! This means before the <html> tag is sent!
<?php header('Origin-Agent-Cluster: ?0'); ?>
2. Setting the header on the server
Set the header e.g. in Apache in a .htaccess file. Create a .htaccess file or modify the existing one on the server that contains the iframe and add the following line there:
Header set Origin-Agent-Cluster "?0"
Summary
Right now this settings are not tested as I do not have a SSL certificate for sub domains for tinywebgallery.com as so far it was not needed and it would double the monthly hosting fees. So please give me feedback you have tested it successful.
To be on the save side please switch to the ai_external.js
Best regards,
Michael