Course List Widget Disappears on Preview

I added a Course List Widget to a page of a site I was working on, the preview displayed it perfectly ok. Then when I had to change the domain to finish up everything, the widget doesn’t load at all in preview. I have Elementor (Free & Pro) updated, along with Tutor LMS and the Elementor Addon. I tried disabling and enabling the plugin, to no avail.

How do I fix this?