Shell navigation to child page and back repeatedly causes blank page on iOS

[aalsamoht]

Description

When navigating from a Shell tab's root page to a child page and back using the Shell back button, repeating this action several times causes the page to go blank. The content disappears but the Shell chrome (tabs, navigation bar) remains visible.

This is reproducible on iOS 26.4.2 (iPhone 13, iPhone 15 Pro) with both .NET 9 and .NET 10. It is not reproducible on Android or on iOS 15.8.7 (iPhone 7). Navigating with animate=false also does not reproduce the issue.

Steps to Reproduce

1. Run the app on an iOS device running iOS 26.4.2 (tested on iPhone 13 and iPhone 15 Pro)
2. On the Home tab, press the Go to child page button
3. Press the Shell back navigation button to return to the Home tab root page
4. Rapidly and repeatedly alternate between the Go to child page button and the Shell back button — place one finger on each and tap as fast as possible
5. After several rapid back-and-forth navigations, the page goes blank

Note: On the Other tab, navigation to the child page uses animate=false and the issue cannot be reproduced.

Link to public reproduction project repository

https://github.com/aalsamoht/ReproBranches/tree/maui/blank-page

Version with bug

10.0.50

Is this a regression from previous behavior?

No, this is something new

Last version that worked well

No response

Affected platforms

iOS

Affected platform versions

iOS 26.4.2

Did you find any workaround?

Navigating with animate=false also does not reproduce the issue. Replace await Shell.Current.GoToAsync($"OtherPageChild"); with await Shell.Current.GoToAsync($"OtherPageChild", false);

Relevant log output

[NGeras]

Facing the same issue on 10.0.60. iOS 26.4.2 (iPhone 15 Pro Max)

While the proposed workaround (animate = false) prevents the issue when rapidly tapping the Shell back button, the problem is still reproducible using the native iOS back gesture.
Specifically, if you repeatedly and quickly swipe from the screen edge to navigate back, the page can still become blank both with animate = true and animate = false.

[aalsamoht]

Facing the same issue on 10.0.60. iOS 26.4.2 (iPhone 15 Pro Max)

While the proposed workaround (animate = false) prevents the issue when rapidly tapping the Shell back button, the problem is still reproducible using the native iOS back gesture. Specifically, if you repeatedly and quickly swipe from the screen edge to navigate back, the page can still become blank both with animate = true and animate = false.

When I use the swipe action to navigate back I eventually get a blank page on the Home tab and an App crash on the Other tab.

Crash report when using swipe navigation on the Other tab

Incident Identifier: 529CD719-6B82-45CA-8F36-263EDB45BC1E CrashReporter Key: dde5c620b59c306aed61c4ce62d393e46ae6e892 Hardware Model: iPhone14,5 Process: MauiBlankPage [777] Path: /private/var/containers/Bundle/Application/CE940667-6355-41D0-A9B8-267C8556CC00/MauiBlankPage.app/MauiBlankPage Identifier: xxx Version: 1.0 (1) Code Type: ARM-64 (Native) Role: Foreground Parent Process: launchd [1] Coalition: xxx [587]

Date/Time: 2026-05-04 15:07:32.6834 +0200
Launch Time: 2026-05-04 15:07:24.7387 +0200
OS Version: iPhone OS 26.4.2 (23E261)
Release Type: User
Baseband Version: 5.51.03
Report Version: 104

Exception Type: EXC_CRASH (SIGABRT)
Exception Codes: 0x0000000000000000, 0x0000000000000000
Termination Reason: SIGNAL 6 Abort trap: 6
Terminating Process: MauiBlankPage [777]

Triggered by Thread: 0

Application Specific Information:
abort() called

Thread 0 name: tid_103 Dispatch queue: com.apple.main-thread
Thread 0 Crashed:
0 libsystem_kernel.dylib 0x251dbf1d0 __pthread_kill + 8
1 libsystem_pthread.dylib 0x20213e7dc pthread_kill + 267
2 libsystem_c.dylib 0x1aee68de4 abort + 147
3 MauiBlankPage 0x102a61924 0x100da8000 + 30120228
4 MauiBlankPage 0x1029dbd9c 0x100da8000 + 29572508
5 libsystem_platform.dylib 0x2c2f0b200 _sigtramp + 55
6 libsystem_pthread.dylib 0x20213e7dc pthread_kill + 267
7 libsystem_c.dylib 0x1aee68de4 abort + 147
8 MauiBlankPage 0x1028981bc 0x100da8000 + 28246460
9 MauiBlankPage 0x102921eac 0x100da8000 + 28810924
10 MauiBlankPage 0x1029b6014 0x100da8000 + 29417492
11 MauiBlankPage 0x1028a0844 0x100da8000 + 28280900
12 MauiBlankPage 0x102a15630 0x100da8000 + 29808176
13 dyld 0x19ff31c1c start + 6927

Thread 1:

Thread 2 name: SGen worker
Thread 2:
0 libsystem_kernel.dylib 0x251dba5e8 __psynch_cvwait + 8
1 libsystem_pthread.dylib 0x202139b48 _pthread_cond_wait + 979
2 MauiBlankPage 0x1028feee0 0x100da8000 + 28667616
3 libsystem_pthread.dylib 0x20213b438 _pthread_start + 135
4 libsystem_pthread.dylib 0x2021378cc thread_start + 7

Thread 3 name: Finalizer
Thread 3:
0 libsystem_kernel.dylib 0x251db4c50 semaphore_wait_trap + 8
1 MauiBlankPage 0x102990a04 0x100da8000 + 29264388
2 MauiBlankPage 0x102970dc8 0x100da8000 + 29134280
3 libsystem_pthread.dylib 0x20213b438 _pthread_start + 135
4 libsystem_pthread.dylib 0x2021378cc thread_start + 7

Thread 4:

Thread 5:

Thread 6 name: com.apple.uikit.eventfetch-thread
Thread 6:
0 libsystem_kernel.dylib 0x251db4cd4 mach_msg2_trap + 8
1 libsystem_kernel.dylib 0x251db830c mach_msg2_internal + 75
2 libsystem_kernel.dylib 0x251db822c mach_msg_overwrite + 423
3 libsystem_kernel.dylib 0x251db8078 mach_msg + 23
4 CoreFoundation 0x1a3353ea4 __CFRunLoopServiceMachPort + 159
5 CoreFoundation 0x1a331df94 __CFRunLoopRun + 1187
6 CoreFoundation 0x1a331d1d0 _CFRunLoopRunSpecificWithOptions + 531
7 Foundation 0x1a0590cf0 -[NSRunLoop(NSRunLoop) runMode:beforeDate:] + 211
8 Foundation 0x1a0590bd8 -[NSRunLoop(NSRunLoop) runUntilDate:] + 63
9 UIKitCore 0x1a8fa6afc -[UIEventFetcher threadMain] + 419
10 Foundation 0x1a0614804 NSThread__start + 731
11 libsystem_pthread.dylib 0x20213b438 _pthread_start + 135
12 libsystem_pthread.dylib 0x2021378cc thread_start + 7

Thread 7:

Thread 8:

Thread 9:

Thread 10 name: com.apple.UIKit.inProcessAnimationManager
Thread 10:
0 libsystem_kernel.dylib 0x251db4cd4 mach_msg2_trap + 8
1 libsystem_kernel.dylib 0x251db830c mach_msg2_internal + 75
2 libsystem_kernel.dylib 0x251db822c mach_msg_overwrite + 423
3 libsystem_kernel.dylib 0x251db8078 mach_msg + 23
4 CoreFoundation 0x1a3353ea4 __CFRunLoopServiceMachPort + 159
5 CoreFoundation 0x1a331df94 __CFRunLoopRun + 1187
6 CoreFoundation 0x1a331d1d0 _CFRunLoopRunSpecificWithOptions + 531
7 Foundation 0x1a0590cf0 -[NSRunLoop(NSRunLoop) runMode:beforeDate:] + 211
8 Foundation 0x1a05952fc -[NSRunLoop(NSRunLoop) run] + 63
9 UIKitCore 0x1a9299c9c 0x1a9299b9d + 255
10 UIKitCore 0x1a8f005c4 0x1a8f005a1 + 35
11 Foundation 0x1a0614804 NSThread__start + 731
12 libsystem_pthread.dylib 0x20213b438 _pthread_start + 135
13 libsystem_pthread.dylib 0x2021378cc thread_start + 7

Thread 11 name: .NET TP Worker
Thread 11:
0 libsystem_kernel.dylib 0x251dba5e8 __psynch_cvwait + 8
1 libsystem_pthread.dylib 0x202139b48 _pthread_cond_wait + 979
2 MauiBlankPage 0x1028ba110 0x100da8000 + 28385552
3 MauiBlankPage 0x1028bd894 0x100da8000 + 28399764
4 MauiBlankPage 0x1010a3760 0x100da8000 + 3127136
5 MauiBlankPage 0x1025dd05c 0x100da8000 + 25383004
6 MauiBlankPage 0x1025db50c 0x100da8000 + 25376012
7 MauiBlankPage 0x1029afee4 0x100da8000 + 29392612
8 MauiBlankPage 0x102960840 0x100da8000 + 29067328
9 MauiBlankPage 0x102970dac 0x100da8000 + 29134252
10 libsystem_pthread.dylib 0x20213b438 _pthread_start + 135
11 libsystem_pthread.dylib 0x2021378cc thread_start + 7

Thread 12 name: .NET TP Gate
Thread 12:
0 libsystem_kernel.dylib 0x251dba5e8 __psynch_cvwait + 8
1 libsystem_pthread.dylib 0x202139b74 _pthread_cond_wait + 1023
2 MauiBlankPage 0x1028a815c SystemNative_LowLevelMonitor_TimedWait + 104
3 MauiBlankPage 0x1012612dc 0x100da8000 + 4952796
4 MauiBlankPage 0x10247fb20 0x100da8000 + 23952160
5 MauiBlankPage 0x1025fdbf8 0x100da8000 + 25517048
6 MauiBlankPage 0x1025fb8c8 0x100da8000 + 25508040
7 MauiBlankPage 0x1025f5348 0x100da8000 + 25482056
8 MauiBlankPage 0x1010a33e4 0x100da8000 + 3126244
9 MauiBlankPage 0x1025db50c 0x100da8000 + 25376012
10 MauiBlankPage 0x1029afee4 0x100da8000 + 29392612
11 MauiBlankPage 0x102960840 0x100da8000 + 29067328
12 MauiBlankPage 0x102970dac 0x100da8000 + 29134252
13 libsystem_pthread.dylib 0x20213b438 _pthread_start + 135
14 libsystem_pthread.dylib 0x2021378cc thread_start + 7

Thread 13 name: .NET TP Worker
Thread 13:
0 libsystem_kernel.dylib 0x251dba5e8 __psynch_cvwait + 8
1 libsystem_pthread.dylib 0x202139b48 _pthread_cond_wait + 979
2 MauiBlankPage 0x1028ba110 0x100da8000 + 28385552
3 MauiBlankPage 0x1028bd894 0x100da8000 + 28399764
4 MauiBlankPage 0x1010a3760 0x100da8000 + 3127136
5 MauiBlankPage 0x1025dd05c 0x100da8000 + 25383004
6 MauiBlankPage 0x1025db50c 0x100da8000 + 25376012
7 MauiBlankPage 0x1029afee4 0x100da8000 + 29392612
8 MauiBlankPage 0x102960840 0x100da8000 + 29067328
9 MauiBlankPage 0x102970dac 0x100da8000 + 29134252
10 libsystem_pthread.dylib 0x20213b438 _pthread_start + 135
11 libsystem_pthread.dylib 0x2021378cc thread_start + 7

Thread 0 crashed with ARM Thread State (64-bit):
x0: 0x0000000000000000 x1: 0x0000000000000000 x2: 0x0000000000000000 x3: 0x0000000000000000
x4: 0xffffffff93b3650a x5: 0x0000000000000008 x6: 0x000000016f056920 x7: 0x000000016f056000
x8: 0x18f907d3405aceb4 x9: 0x18f907d14d13ef74 x10: 0x0000000000000002 x11: 0x00000000fffffffd
x12: 0x0000000000000000 x13: 0x0000000000000000 x14: 0x0000000000000000 x15: 0x0000000000000000
x16: 0x0000000000000148 x17: 0x000000020d4921c0 x18: 0x0000000000000000 x19: 0x0000000000000006
x20: 0x0000000000000103 x21: 0x000000020d4922a0 x22: 0x0000000103e82400 x23: 0x0000000000000001
x24: 0x0000000103c33840 x25: 0x0000000000000000 x26: 0x0000000000000000 x27: 0x000000016f057c67
x28: 0x0000000103c6c1c0 fp: 0x000000016f056930 lr: 0x000000020213e7dc
sp: 0x000000016f056910 pc: 0x0000000251dbf1d0 cpsr: 0x40001000
far: 0x0000000000000000 esr: 0x56000080 (Syscall)

Binary Images:
0x100da8000 - 0x102babfff MauiBlankPage arm64 <43c5c61f83c93ebbb8074cf40957ce58> /private/var/containers/Bundle/Application/CE940667-6355-41D0-A9B8-267C8556CC00/MauiBlankPage.app/MauiBlankPage
0x1066e4000 - 0x1066effff libobjc-trampolines.dylib arm64e /private/preboot/Cryptexes/OS/usr/lib/libobjc-trampolines.dylib
0x251db4000 - 0x251defac7 libsystem_kernel.dylib arm64e <5f4e68e1021c3a8fa6f62c4c077d0676> /usr/lib/system/libsystem_kernel.dylib
0x202137000 - 0x2021434ef libsystem_pthread.dylib arm64e <6c9bcde9819d345d9d71b60ad47e5159> /usr/lib/system/libsystem_pthread.dylib
0x1aedf2000 - 0x1aee7130f libsystem_c.dylib arm64e <08196a2fb3fa3d0bb151ad50a6d0a0b4> /usr/lib/system/libsystem_c.dylib
0x2c2f07000 - 0x2c2f0f3a3 libsystem_platform.dylib arm64e <56427ac9a3b83c26b7ab941348e1faea> /usr/lib/system/libsystem_platform.dylib
0x19ff2d000 - 0x19ffd1ebf dyld arm64e <80dd1800f68d354f81068cb5ea621aca> /usr/lib/dyld
0x0 - 0xffffffffffffffff ??? unknown-arch <00000000000000000000000000000000> ???
0x1a32ef000 - 0x1a388b0ff CoreFoundation arm64e <11f13078e01b343ba0208d60bae7bbb6> /System/Library/Frameworks/CoreFoundation.framework/CoreFoundation
0x1a0586000 - 0x1a140e45f Foundation arm64e <66bf417c1d003457a302196bbaec23d0> /System/Library/Frameworks/Foundation.framework/Foundation
0x1a8ec0000 - 0x1ab3ff3bf UIKitCore arm64e <32c1b300a6013e148b533419a2d2f234> /System/Library/PrivateFrameworks/UIKitCore.framework/UIKitCore

EOF

[NGeras]

In Sentry, I got this log when a crash occurred during rapid back navigation. Maybe this helps identify the root cause of this bug.

Nav Stack consistency error

System.Exception

Nav Stack consistency error

in async void ShellSection.Microsoft.Maui.Controls.IShellSectionController.SendPopping(Task poppingCompleted) [external]

no source context available

in void Task.ThrowAsync(Exception exception, SynchronizationContext targetContext)+(object state) => { } [external]

no source context available

/Users/builder/azdo/_work/2/s/macios/src/Foundation/NSAction.cs:165 in void NSAsyncSynchronizationContextDispatcher.Apply() [in-app]

no source context available

in void __Registrar_Callbacks__.callback_4150_Foundation_NSAsyncSynchronizationContextDispatcher_Apply(IntPtr pobj, IntPtr sel, IntPtr* exception_gchandle) [in-app]

no source context available

[kklose23]

Additional findings + iOS simulator repro

Investigated on .NET 10 MAUI Shell.

Repro (iPhone 16 simulator, iOS 26.x)

1. Shell with tab roots and pushed routes (e.g. HomePage tab → push DetailPage)
2. Push to a detail page
3. Navigate back — back button, swipe gesture, or tapping the tab bar item all reproduce
4. Immediately tap to push to a detail page again while the back is still in-flight
5. Repeat 3–10 times

Tab page goes blank — Shell chrome remains, content does not render. Tab switching doesn't recover it; user has to kill the app.

Internal state at the moment of the blank

• Shell.CurrentState.Location is stale (e.g. //HomePage/DetailPage) while Shell.CurrentPage is already the tab root (HomePage).
• Handler and Handler.PlatformView on the tab root are both null.
• Shell.CurrentPage == thisPage, but the page is disconnected from the platform view tree.

Recovery from outside MAUI is difficult

• Shell.GoToAsync($"//{route}") to the same route silently short-circuits.
• Resetting ShellContent.ContentTemplate + bouncing through another tab crashes with ObjectDisposedException in ShellSectionRenderer.SendPop.

Workaround (iOS, Push only)

In Shell.Navigating, compare Shell.CurrentState.Location's last URL segment to Shell.CurrentPage.GetType().Name. If they don't match, cancel the Push.

#if IOS
if (args.Source == ShellNavigationSource.Push)
{
    var lastSegment = LastSegmentOf(args.Current.Location.OriginalString);
    var currentPageType = Shell.Current.CurrentPage.GetType().Name;
    if (!string.IsNullOrWhiteSpace(lastSegment) &&
        !string.Equals(lastSegment, currentPageType, StringComparison.Ordinal))
    {
        args.Cancel();
        return;
    }
}
#endif

Requires routes registered as nameof(PageType) so URL segments match type names.

Possibly related: #34662

Shell.Navigated is also skipped during rapid navigation, which broke earlier timing-based workarounds. Fixed in PR #34880 for .NET 10 SR7. The stale CurrentState.Location we observed looks similar — possibly a shared root cause.

Also reported in this thread (not pursued): animate: false on GoToAsync reportedly avoids the bug.