Hello – I cannot get the customize preview to show on my new site. It’s just a big white/gray box.
I’ve done some searching and I’ve tried the solutions already suggested in some other threads, to no success.
I deactivated all plugins, then reactivated them one by one. I had my host whitelist ModSecurity. I still can’t get it to show. In the menu bar, the title of the page is still showing as Customize: Loading… suggesting it’s a loading error perhaps?