Hey, I’ve been using Happyfiles Pro gallery in Gutenberg recently to have the lightbox feature, but one drawback is that I can’t find a way to modify the layout for different breakpoints (typically the number of columns).
I know I’m not helping you much with this comment, since it’s not perfect, but still if you’re using Happyfiles already, I recommend you try the happyfiles gallery block that’s available to you in Gutenberg. It might be enough for your needs !