Safari 26 lets websites feel more like native apps on your iPhone and iPad....

https://bizzmarkblog.com/why-does-my-ipad-web-app-feel-different-from-the-same-site-in-safari-tabs/

Safari 26 lets websites feel more like native apps on your iPhone and iPad. When you add a site to your Home Screen, it opens without browser bars or tabs, giving you a cleaner, full-screen view