Not every minor iOS version update includes changes in the Web platform. Still, iOS 15.4 will be an exception: we have 1) for the first time in 7 years, the appearance of Web Push for iOS (but wait for the fine print), 2) after three years of Web App Manifest support, we finally have support for the icons members, and 3) many new APIs such as WebXR (for virtual and augmented reality) are available.
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