Ben Lang, writing for Road to VR:

In a somewhat surprising move, Apple confirmed that Safari on Vision Pro will support WebXR. Prior to the reveal of the headset, it was an open question whether the company would entertain the idea of XR experiences through the browser, and even more so if the company would adopt the relatively new WebXR standard. But now Apple has confirmed that Safari on Vision Pro will indeed support WebXR.

The company confirmed as much in its WWDC 2023 developer talk titled Meet Safari for Spatial Computing, in which Apple explained the version of Safari running on Vision Pro “truly is Safari with the same WebKit engine underneath, plus some thoughtful additions for Vision Pro.”

Thanks to Safari on visionOS being a fully-featured version of the browser, existing websites should work exactly as expected, the company says. But to go beyond flat web pages, Safari on visionOS includes support for WebXR for immersive experiences and the new <model> tag for 3D models.

This isn't really much of a surprise over all. Think of browsing the web on mobile phones before Apple released the iPhone compared to where it is today, and you wouldn't be suprised either.