Cornerstone Error – The preview could not load due to the iframe response being incomplete. This is most often related to a plugin conflict, or customizations introducing a PHP error

[MLTV-Webmaster]

I’m getting this error when I load a page on the backend that is using Cornerstone. I’ve noticed several people have had the same issue recently. Any idea what is causing it?

[nico]

Hi @MLTV-Webmaster,

Thanks for writing in.

This thread below is a good thread that could fix that problem.

Cornerstone fails to open editor on any post/page

If still not helping, share us admin credentials so we could check your setup closer.

Don’t forget to set it in a secure note.

Thanks.