Environment App built with Xcode 26.3 (iOS 26 SDK) Deployment Target: iOS 16+ Issue occurs only on devices upgraded to iOS 27. Works perfectly on iOS 26.x. Problem description: After end‑user upgrades their iPhone to iOS 27, a persistent stale frosted‑glass / blur rendering effect appears at the top area of screens. This symptom occurs both on native UITableView and inside WKWebView. No blur‑related code (UIVisualEffectView / backdrop‑filter) is added by our application. Layout frames, insets and contentOffset are all correct. Reproduction hints: The issue can be triggered after presenting then dismissing a WKWebView which loads H5 with overlay popup. Rendering state seems to leak to the whole app process. The leftover blur remains until push/pop the view controller. Is this an iOS 27 system bug, or do we need special adaptation for existing apps built with older Xcode 26.3 SDK? What is the proper workaround for apps compiled with Xcode26.3, since liquidGlassEffectEnabled is only available in iOS27 SDK and cannot be accessed in our current build environment.