Odd image behavior

When I add a featured image to a menu item, it does not show up. the space is there and I see it in the source code but it does not display. I am using Windows 10 and an iPad with safari to test. On windows 10 I used Chrome, Firefox and Edge to test. When I insert the image into a Edit Menu Item post, it works fine as an inline image with the text in the post. It works for a workaround. But nothing I have tried will get the featured image to show. I have deleted it and tried again. Put in several other menu items to see if that worked. Nothing. no featured images are displaying.

https://ww.wp.xz.cn/plugins/quick-restaurant-menu/