have the same issue, unreal version 5.3:
LogOutputDevice: Error: === Handled ensure: ===
LogOutputDevice: Error: Ensure condition failed: InDescriptor.ChunkFragments.IsEmpty() [File:D:\build\++UE5\Sync\Engine\Plugins\Runtime\MassEntity\Source\MassEntity\Private\MassEntityManager.cpp] [Line: 761]
LogOutputDevice: Error: Removing chunk fragments is not supported
LogOutputDevice: Error: Stack:
LogOutputDevice: Error: [Callstack] 0x000001eb1fa873e1 UnrealEditor-MassEntity.dll!FMassEntityManager::RemoveCompositionFromEntity() [D:\build\++UE5\Sync\Engine\Plugins\Runtime\MassEntity\Source\MassEntity\Private\MassEntityManager.cpp:761]
LogOutputDevice: Error: [Callstack] 0x000001eb684f60e0 UnrealEditor-MassActors.dll!UE::Core::Private::Function::TFunctionRefCaller<`UMassAgentSubsystem::UnregisterAgentComponent'::`24'::<lambda_7>,void __cdecl(FMassEntityManager &)>::Call() [D:\build\++UE5\Sync\Engine\Source\Runtime\Core\Public\Templates\Function.h:480]
LogOutputDevice: Error: [Callstack] 0x000001eb684fb498 UnrealEditor-MassActors.dll!FMassDeferredCommand<3>::Execute() [D:\build\++UE5\Sync\Engine\Plugins\Runtime\MassEntity\Source\MassEntity\Public\MassCommands.h:567]
LogOutputDevice: Error: [Callstack] 0x000001eb1fa67769 UnrealEditor-MassEntity.dll!FMassCommandBuffer::Flush() [D:\build\++UE5\Sync\Engine\Plugins\Runtime\MassEntity\Source\MassEntity\Private\MassCommandBuffer.cpp:153]
LogOutputDevice: Error: [Callstack] 0x000001eb1fa679ef UnrealEditor-MassEntity.dll!FMassEntityManager::FlushCommands() [D:\build\++UE5\Sync\Engine\Plugins\Runtime\MassEntity\Source\MassEntity\Private\MassEntityManager.cpp:1429]
LogOutputDevice: Error: [Callstack] 0x000001eb1fa64076 UnrealEditor-MassEntity.dll!TGraphTask<UE::Mass::Executor::FMassExecutorDoneTask>::ExecuteTask() [D:\build\++UE5\Sync\Engine\Source\Runtime\Core\Public\Async\TaskGraphInterfaces.h:1265]
LogOutputDevice: Error: [Callstack] 0x00007ffea2341c9f UnrealEditor-Core.dll!FNamedTaskThread::ProcessTasksNamedThread() [D:\build\++UE5\Sync\Engine\Source\Runtime\Core\Private\Async\TaskGraph.cpp:758]
LogOutputDevice: Error: [Callstack] 0x00007ffea23422ae UnrealEditor-Core.dll!FNamedTaskThread::ProcessTasksUntilQuit() [D:\build\++UE5\Sync\Engine\Source\Runtime\Core\Private\Async\TaskGraph.cpp:649]
LogOutputDevice: Error: [Callstack] 0x00007ffea234eeb0 UnrealEditor-Core.dll!FTaskGraphCompatibilityImplementation::WaitUntilTasksComplete() [D:\build\++UE5\Sync\Engine\Source\Runtime\Core\Private\Async\TaskGraph.cpp:2125]
LogOutputDevice: Error: [Callstack] 0x00007ffe6d5075aa UnrealEditor-Engine.dll!FTickTaskSequencer::ReleaseTickGroup() [D:\build\++UE5\Sync\Engine\Source\Runtime\Engine\Private\TickTaskManager.cpp:556]
LogOutputDevice: Error: [Callstack] 0x00007ffe6d510bfe UnrealEditor-Engine.dll!FTickTaskManager::RunTickGroup() [D:\build\++UE5\Sync\Engine\Source\Runtime\Engine\Private\TickTaskManager.cpp:1583]
LogOutputDevice: Error: [Callstack] 0x00007ffe6c5c9839 UnrealEditor-Engine.dll!UWorld::RunTickGroup() [D:\build\++UE5\Sync\Engine\Source\Runtime\Engine\Private\LevelTick.cpp:771]
LogOutputDevice: Error: [Callstack] 0x00007ffe6c5d67a2 UnrealEditor-Engine.dll!UWorld::Tick() [D:\build\++UE5\Sync\Engine\Source\Runtime\Engine\Private\LevelTick.cpp:1515]
LogOutputDevice: Error: [Callstack] 0x00007ffe7c6558f8 UnrealEditor-UnrealEd.dll!UEditorEngine::Tick() [D:\build\++UE5\Sync\Engine\Source\Editor\UnrealEd\Private\EditorEngine.cpp:1924]
LogOutputDevice: Error: [Callstack] 0x00007ffe7d2aea06 UnrealEditor-UnrealEd.dll!UUnrealEdEngine::Tick() [D:\build\++UE5\Sync\Engine\Source\Editor\UnrealEd\Private\UnrealEdEngine.cpp:531]
LogOutputDevice: Error: [Callstack] 0x00007ff6c0678af2 UnrealEditor.exe!FEngineLoop::Tick() [D:\build\++UE5\Sync\Engine\Source\Runtime\Launch\Private\LaunchEngineLoop.cpp:5825]
LogOutputDevice: Error: [Callstack] 0x00007ff6c069d28c UnrealEditor.exe!GuardedMain() [D:\build\++UE5\Sync\Engine\Source\Runtime\Launch\Private\Launch.cpp:188]
LogOutputDevice: Error: [Callstack] 0x00007ff6c069d37a UnrealEditor.exe!GuardedMainWrapper() [D:\build\++UE5\Sync\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:118]
LogOutputDevice: Error: [Callstack] 0x00007ff6c06a0854 UnrealEditor.exe!LaunchWindowsStartup() [D:\build\++UE5\Sync\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:258]
LogOutputDevice: Error: [Callstack] 0x00007ff6c06b6984 UnrealEditor.exe!WinMain() [D:\build\++UE5\Sync\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:298]
LogOutputDevice: Error: [Callstack] 0x00007ff6c06b9d7a UnrealEditor.exe!__scrt_common_main_seh() [D:\a\_work\1\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288]
LogOutputDevice: Error: [Callstack] 0x00007fff0483259d KERNEL32.DLL!UnknownFunction []
LogOutputDevice: Error: [Callstack] 0x00007fff0582af38 ntdll.dll!UnknownFunction []
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