On iOS 26, QuickLookAR (ARQuickLookPreviewItem) shares the actual .usdz file via the system Share Sheet instead of the original website URL.
This is a regression from iOS 17–18, where sharing correctly preserved and sent only the source URL.
Repro steps: 1. Open a web-hosted USDZ model in QuickLookAR (Safari). 2. Tap Share. 3. Share via any messenger. 4. The full .usdz file is sent.
Expected: Share Sheet sends only the original URL.
Actual: Share Sheet sends the USDZ file.
Impact: Uncontrolled distribution of proprietary 3D assets. Critical IP / data leak. Blocks production AR deployments relying on QuickLook.
Environment: iOS 26.0–26.1, iPhone 14 / 15. Works as expected on iOS 17–18.
Test case: https://admixreality.com/ios26/