Hello,
I found that the same problem have the product gallery images in swiper slide of product view. Sometimes they are shown under the main product image, sometimes not. Before the last updates there was no such problem.
Edit: I think it may be a problem related to lazy loading. In a page, where I use the elementor addon “Products” with Grid Display type, I had Lazy Loading for Navigation. Now it stopped to load more than one row. I turned off the Navigation and now it load all rows. So, it maybe some issue like this in slider and product images.