I have no idea why this happens, maybe all the costumes are stored on a blocked site? Maybe it’s because they are all loaded at once and that is too much data?
It could maybe be fixed by having the costumes load from top to bottom instead of all at once, or by hosting the costumes on the website itself.
I’m using safari, and my school issued I pad (9th generation)
The costumes are indeed stored on the snap website itself. And just to clear things up, any browser on ios uses the safari engine, even if you're using chrome. This is just apple being apple, so there isn't much you can do.
As for the costumes loading slowly, that could just be your internet being slow, because when I try it with my ipad pro (10.5 inch) on ios 15.3.1, the costumes load just fine.