I have created a new theme and i use it in some of my sites (multisite) but at one site the customizer preview does not load (spinner never stops). Loading the customizer preview of other themes work just my theme does not work.
There is no error in the console of the chrome development tools.
So i tried a few things...
- renamed the theme (folder and inside the style.css)
- removed ALL files so that just an empty index.php and a style.css, that only contains the necessary comment, was left
But it does load, again, just at one of my multisites.
How can i debug this? Any ideas?