visionOS26Beta3toBeta4.md

visionOS 26 Beta 3 to Beta 4 Changelog

New Features Added in Beta 4

Foundation Models Framework

• LanguageModelSession.prewarm() now caches instructions and prefix of prompts, reducing time to first-generated token (152381043)
• #Playground in Xcode now allows filing feedback for Foundation Models framework responses (153770707)
• Content Tagging now supports non-English languages with SystemLanguageModel(useCase: .contentTagging).supportedLanguages (155801948)

WebKit API (New Section)

• Load APIs on WebPage now return AsyncSequence directly for tracking navigation events (152414525)
• Direct URL loading support added to WebPage API with default baseURL parameter for HTML strings (152904248)

Window Sharing (New Section)

• People View Integration - Window sharing can now be started and managed from People View, including nearby people invitations and session management (154800877)

Issues Resolved (Moved from Known Issues to Resolved Issues)

App Store

• Fixed: iPhone performance gaming tier apps now available via TestFlight (141472382)

ARKit

• Fixed: Data provider state changes now update individually as intended (152665341)
• Fixed: Hand anchor queries with timestamps far from trackable anchor time (153125027)

Foundation Models Framework

• Fixed: Generable types with recursive definitions (153147722)
• Fixed: Chinese language prompts causing "Unsupported language zh-hans" error (153151710)
• Fixed: LanguageModelSession creation with duplicate tool names (153426645)
• Fixed: Session transcript tools not being used properly (154904647)
• Fixed: Guardrail violation errors on valid prompts (155273863)

Quick Look

• Fixed: Side-by-side stereo 180° video conversion to Apple Projected Media Profile stalling (146349661)

StoreKit

• Fixed: SKProduct decoding failures in StoreKit Testing (150851879)
• Fixed: Transaction completion issues causing subsequent purchase failures (155449267)

Swift Charts

• Fixed: Annotations on scrollable charts being clipped (109164195)

SwiftUI

• Fixed: Two-handed gestures canceling initial event stream (149026305)

WidgetKit

• Fixed: iOS-based widgets not appearing automatically during development in Xcode (154678847)

New Known Issues Added in Beta 4

CompositorServices

• Hover effects may not work on tracking areas with shared layout renderers (155811050)

EyeSight (New Section)

• EyeSight might not display content even when observer is present (155800405)

Foundation Models Framework

• Guided generation with tool calling may cause decoding failures (153773704)
• Tools might not get called when using tool calling with guided generation (155313086)

iPhone Unlock (New Section)

• iPhone unlocking with Apple Vision Pro may not work (155556946)

Music

• Music widget might be unable to display content artwork (155628172)

Safari

• MSE video in immersive mode may prevent exiting immersive mode (155925753)

WebKit

• USDZ models with compressed textures might render without textures in HTML <model> elements (155650658)

Additional Resolved Issues in Beta 4

RealityKit

• Fixed: VideoPlayerComponent API Dynamic Mask support in visionOS simulator (152725380)

WebKit API

• Fixed: webViewOnScrollGeometryChange reporting incorrect content size (146576790)

Issue Reference Changes

RemoteImmersiveSpace

• Travel mode spatial stream issue reference updated from (151941176) to (154209388)

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Summary: Beta 4 primarily focuses on resolving many known issues from Beta 3, particularly in Foundation Models framework, ARKit, and various UI components. Three new major feature areas were introduced: enhanced Foundation Models capabilities, WebKit API improvements, and Window Sharing through People View. Several new issues were also identified, mainly related to EyeSight, iPhone Unlock functionality, and rendering/display problems.