I’m running into an issue when attempting to edit Global Blocks where the preview won’t load. This only happens with Global Blocks, and not Headers, Footers, Layouts or other cornerstone pages. It gives me this 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.
There is also a warning message in the console:
Frame missing CORNERSTONE_FRAME signature. This could mean WordPress did not shutdown properly or this URL could be cached even though Cache Control headers are present.
What I’ve tried:
- Disabling all plugins to check if one of the plugins was the problem.
- Reverting to a previous version of PHP (7.2.1).
- Making sure the Theme was up to date.
- Reverting to the parent theme.
Current site setup:
Hosting: Siteground
PHP Version: 7.4.21
Theme: X Pro Child Theme (4.3.3)
Other forum posts I’ve looked at from people that had the same problem:
Unfortunately, the above posts have not helped me. I’m not sure where to go from here or what to try. Can anyone help me fix this problem? I’ve attached a secure note with login credentials to the site so Themeco staff can get in and look around if that helps.