Hi,
Recently I connect the my company public wifi. The Captive Portal Opens very slow. (30 - 40 seconds)
But Other Platforms like android and windows captive portal opens quickly.
I am using iPhone 12 mini with latest iOS 15.3. I read old apple forums, apple have this issue with iOS 12 and fixed in iOS 13. I cannot found this is OS issue or network issue. But other platforms showing captive portal very quickly.
Reference URL : https://github.com/tzapu/WiFiManager/issues/868