Personally I sort that under "miscellaneous Safari awfulness" since the Safari browser causes all sorts of seemingly random problems on all kinds of sites. Even

Personally I sort that under "miscellaneous Safari awfulness" since the Safari browser causes all sorts of seemingly random problems on all kinds of sites. Even more randomness when you add in Safari Extensions, which also randomly break on random sites at random (non-reproducible) times, in my experience. Alternative browsers on iOS can't come soon enough.