This element could not be render... in all pages

A few days ago I moved a website to Wordpress.com and now I get the message:
This element could not be render due to invalid markup. You may have enclosed HTML tags in your content for every element in the page as soon as I make any changes to the page.
Here is a link to a video showing what happens.
https://drive.google.com/file/d/1uDVoWjn89csd1-IcCx7D1uEAYpdglmdJ/view?usp=sharing
It happens with all pages, or even if I want to edit just a single component.
All these pages and components worked perfectly before the move.
Can you help me figure out what is happening here?
Thanks,
Patrick
PS: I will give you access to the site in a secure note.

Hello Patrick,

Thanks for writing in! The issue is caused by the React JS script. It could be coming from a 3rd party plugin having in conflict with the builder. Please do a plugin conflict test by temporarily deactivating the 3rd party plugins one at a time. For more troubleshooting, please check this out:

You may also clear your plugin cache or test for a plugin amongst other things. Kindly troubleshoot for the most common issues that could caused the issue on your site:

Best Regards.

Thanks. Found the culprit: Real Media Library by devowl.io

Hi Patrick,

Glad to know that you were able to find the cause of the issue.

Thanks