[dvcrn]

On top of that, Safari state is shared in a lot of embedded browser windows inside apps, which no other browser can obviously implement

[pilif]

They had to limit this quite a bit because it was abused for tracking.

SFSafariViewController now has its own cookie store too unless you use a specific API for authentication purposes, but that will also open a modal dialog the user has to confirm.

This is why we can't have nice things.