Cannot remove an observer <FLEXExplorerViewController 0x10aa28570> for the key path "frame" from <LWindow 0x11011e800> because it is not registered as an observer.

[PONCE54958]

(Crash in Lockscreen using FLEXing)

Date: 1/20/20, 4:43 PM
Process: SpringBoard
Bundle id: com.apple.springboard
Device: iPhone XS Max, iOS 12.4
 
Exception type: NSRangeException
Reason: Cannot remove an observer <FLEXExplorerViewController 0x10aa28570> for the key path "frame" from <LWindow 0x11011e800> because it is not registered as an observer.
Culprit: libFLEX.dylib
Call stack:
0   CoreFoundation     0x1c4a7ead0 __exceptionPreprocess
1   libobjc.A.dylib    0x1c3c83d00 objc_exception_throw
2   CoreFoundation     0x1c49842f4 -[NSCache init]
3   Foundation         0x1c5437f98 -[NSObject(NSKeyValueObserverRegistration) _removeObserver:forProperty:]
4   Foundation         0x1c5437d50 -[NSObject(NSKeyValueObserverRegistration) removeObserver:forKeyPath:]
5   libFLEX.dylib      0x109dbbc04 -[FLEXExplorerViewController stopObservingView:]
6   libFLEX.dylib      0x109dbb010 -[FLEXExplorerViewController setViewsAtTapPoint:]
7   libFLEX.dylib      0x109dbb308 -[FLEXExplorerViewController setCurrentMode:]
8   libFLEX.dylib      0x109dbcc88 -[FLEXExplorerViewController closeButtonTapped:]
9   libobjc.A.dylib    0x1c3c7f760 -[NSObject performSelector:withObject:withObject:]
10  UIKitCore          0x1f1ea6e88 -[UIApplication sendAction:to:from:forEvent:]
11  UIKitCore          0x1f192b1dc -[UIControl sendAction:to:forEvent:]
12  UIKitCore          0x1f192b510 -[UIControl _sendActionsForEvents:withEvent:]
13  UIKitCore          0x1f192a524 -[UIControl touchesEnded:withEvent:]
14  UIKitCore          0x1f1edfd28 -[UIWindow _sendTouchesForEvent:]
15  UIKitCore          0x1f1ee0f60 -[UIWindow sendEvent:]
16  UIKitCore          0x1f1ec01e8 -[UIApplication sendEvent:]
17  UIKitCore          0x1f1f8b3e8 __dispatchPreprocessedEventFromEventQueue
18  UIKitCore          0x1f1f8dba4 __handleEventQueueInternal
19  UIKitCore          0x1f1f8df14 __handleEventQueueInternal
20  UIKitCore          0x1f1f8df14 __handleEventQueueInternal
21  UIKitCore          0x1f1f8df14 __handleEventQueueInternal
22  UIKitCore          0x1f1f86c5c __handleHIDEventFetcherDrain
23  CoreFoundation     0x1c4a0eb54 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__
24  CoreFoundation     0x1c4a0ead0 __CFRunLoopDoSource0
25  CoreFoundation     0x1c4a0e38c __CFRunLoopDoSources0
26  CoreFoundation     0x1c4a09060 __CFRunLoopRun
27  CoreFoundation     0x1c4a08964 CFRunLoopRunSpecific
28  GraphicsServices   0x1c6c49d8c GSEventRunModal
29  UIKitCore          0x1f1ea5758 UIApplicationMain
30  FrontBoard         0x1dabee11c FBSystemAppMain
31  SpringBoard        0x103088da4 SpringBoard + 2051492
32  libdyld.dylib      0x1c44c4fd8 start

[NSExceptional]

I'm unable to reproduce this, can you reproduce it consistently?

[PONCE54958]

You could reproduce that using flexall or flexing etc, open control center, enable flexall etc, select something and clic on close button, you will the crash

[NSExceptional]

Do you have an iOS 13 device you can try it on? I don't have an iOS 12 device

[PONCE54958]

I could try on the 6s plus with iOS 13

[NSExceptional]

Please! And if you can reproduce it, can you upload a video or gif of you doing it?

streamable.com can host videos