Question:
I made a menu in the desktopversion within a lightbox which works fine. In the mobile version I only see the box (background) but not the menu. Neither in the editor nor on the phone. Any Idea?
Product:
Wix Studio Editor
What are you trying to achieve:
A solution 
What have you already tried:
I tried different sizes of text and lightbox.
Thx!
Have you explored the option of using a hamburger menu? It has a lot of the functionality out of the box, without the need to use a lightbox - Studio Editor: Using Hamburger Menus | Help Center | Wix.com
That being said, are you able to share a screenshot of the editor with the lightbox open on the mobile breakpoint? Will help to see what might be happening 
