似乎在最新的iOS版本11.4中，此问题已解决，我认为现在Safari可以在浏览器和PWA之间共享上下文，例如从PWA***享可以通过Safari浏览器访问Cookie. 但是我认为，当您打开PWA并登录到浏览器中时，您将被重定向到登录(Safari浏览器打开)时仍然存在问题(iOS不会返回PWA，但这是第一步)

It seems that with the last iOS version 11.4 this issue is solved, I think that now safari shares the context between the browser and the PWA and for example from PWA cookies can be accessed throw safari. But I think there's still an issue when you open the PWA and you are being redirect to login (safari opens) once you're log in you stay in the browser (iOS does not return to the PWA, but this is a first step)