Safari 26 helps websites feel more like apps when you use them on iPhone and...

https://delta-wiki.win/index.php/What_Changed_in_Safari_26_for_Add_to_Home_Screen_Websites

Safari 26 helps websites feel more like apps when you use them on iPhone and iPad. When you add a site to your Home Screen, it can now open in a cleaner, app-like view without the usual browser bars