I’m having an issue where updating from Cornerstone 4.2.3 to any of the 5.x versions breaks the inspector pane as soon as I click something in the preview pane.
I can use the Outline tool to add elements and I can see them appearing in the preview but as soon as I click the search icon in an element (still in the outline tool on the left hand of the screen) I get a loading circle (in 5.33 a circle, in 5.0.11 & 5.1.5 the outline remains totally empty) but nothing else.
I get no errors in the JS console (Firefox & Chrome) and no failed loading urls of any kind.
I do get an error in the JSON response when saving the document that says “No response for path: save”
Switching to the X-theme instead of the X-child does not help. Disabling any / all plugins does not help. Reverting to the default .htaccess does not help.
It is probably worthy to mention that the site is part of a multisite environment and all sites using Cornerstone 5.x suffer the same fate. The only plugin I could not disable is the WordPress MU Domain Mapping plugin.
Can you give any hints or tips on how to debug / fix this?