Recently I am unable to edit any posts built using the Cornerstone builder - pages are still editable. Attempting to edit a post generates the following on screen message:
“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.”
The PHP logs report the following errors:
2022/06/15 20:38:57 [error] 8351#8351: *2549727 FastCGI sent in stderr: “PHP message: PHP Fatal error: Uncaught Error: Cannot use object of type WP_Error as array in /public/wp-content/themes/pro/cornerstone/includes/classes/dynamic-content/class-dynamic-content.php:361
#0 /public/wp-content/themes/pro/cornerstone/includes/classes/dynamic-content/class-dynamic-content.php(334): Cornerstone_Dynamic_Content->get_first_term_for_post(Object(WP_Post))
#1 /public/wp-content/themes/pro/cornerstone/includes/classes/dynamic-content/class-dynamic-content.php(322): Cornerstone_Dynamic_Content->get_cached_first_term_for_post(Object(WP_Post))
#2 /public/wp-content/themes/pro/cornerstone/includes/classes/app/class-preview-rendering.php(218): Cornerstone_Dynamic_Content->get_contextual_term()
#3 /public/wp-content/themes/pro/cornerstone/includes/classes/app/class-preview-rendering.php(185): Cornerstone_Preview_Renderi” while reading response header from upstream
I’ve already tried turning off all plugins and child themes so it is just the Pro Theme v 5.1.5 on WordPress 5.9.3.
Any insight or ideas would be greatly appreciated.