Prerequisites

• I have searched for similar issues in both open and closed tickets and cannot find a duplicate.
• The issue still exists against the latest stable version of Elementor.

Description

I have used Nextgen Gallery with Elementor for over a year but the new release of Elementor causes an error preview could not be loaded. All add-ons work ok.

Steps to reproduce

Isolating the problem

• This bug happens with only Elementor plugin active (and Elementor Pro).
• This bug happens with a default WordPress theme active.
• I can reproduce this bug consistently using the steps above.

Environment