Environment
- Xcode 27.1 (27A9269)
- Simulator runtime: iOS 27.1 (24A94401)
- Device: iPhone Duo simulator (unfolded)
- macOS 26.7.1 (25G241), Apple silicon Mac
- Hardware keyboard connected (default Simulator setting)
Summary After locking the iPhone Duo simulator with ⌘L and unlocking it, the whole display stays dimmed and appears unresponsive. Both apps in split view are affected. Pressing the ⌘ key once restores the screen immediately.
This reproduces with only system apps (Settings + Safari), so it does not appear to be app-specific.
Steps to reproduce
- Boot the iPhone Duo simulator (iOS 27.1) and unfold it.
- Open Settings and Safari side by side in split view.
- Press ⌘L to lock the device.
- Unlock (swipe up on the lock screen).
Expected The display returns to normal brightness and both apps respond to input.
Actual
- The entire display, including both split-view apps, stays dimmed.
- Taps appear to do nothing while it is dimmed.
- Pressing ⌘ once immediately restores normal brightness.
- After recovering, Settings had navigated to a different page, which suggests some taps were delivered while the screen was dimmed.
Notes
- It looks like the simulator misses the ⌘ key-up when ⌘L locks the device, so iOS behaves as if ⌘ is still held (the hold-⌘ shortcut overlay dimming the screen).
- Locking with Device ▸ Lock from the Simulator menu avoids the ⌘ modifier entirely.
- In one case the dimmed state persisted across relaunching an app and only cleared after rebooting the simulator.
- We first hit this while testing our own app in split view, where it looked like an app hang. Sampling the app's process showed the main thread idle.
Workaround Press ⌘ once after unlocking, or lock with Device ▸ Lock instead of ⌘L.
Has anyone else seen this on the iPhone Duo simulator, or is this a known issue?