With the latest Pro update modals fail to render on the backend preview with the message “This element failed to render. Additional information may be found in your browsers developer tools.”
I noticed a thread here that says that you are aware of the issue and that it is related to WP5.7 update. That said, it is happening to me on a site running Pro 4.2.3 and WP 5.4.2 and another site running 4.2.3 WP 5.7.

Appears to only be happening with the content area modal (at least on my end).
Thanks.

