Editor crashes if a sublevel with a landscape is duplicated then added to the persistent level as a sublevel.

If a sublevel is duplicated and contains a landscape, the editor will crash when the duplicate level is added to the persistent level as a sublevel.

Frequency 4/4

Regression (yes) issue (does not) occur in 4.12.5

Note In 4.12.5 the user must ctrl+c/ctrl+v to duplicate level in content browser, the duplicate option is not available in 4.12.5.

1. Open Editor (any project)
2. Save Map
3. Open Window>Levels>Levels>Add New>name "test">save
4. Ensure "test" is current level
5. Modes>Landscape Mode>Create
6. RMB "test" in content browser>duplicate
7. Window>Levels>Levels>Add Existing>"test_2">Open

Results

Editor crashes

Expected

Duplicate level is added to levels browser, duplicate landscape shown in level viewport.

MachineId:409D523543AE785961A2788C698A2F90
EpicAccountId:1558531203f84e81b70959b8a59badef

Assertion failed: !LandscapeActor || LandscapeActor == Landscape [Link Removed] [Line: 1784]

UE4Editor_Core!FDebug::AssertFailed() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\private\misc\outputdevice.cpp:421]
UE4Editor_Landscape!ULandscapeInfo::RegisterActor() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\landscape\private\landscape.cpp:1785]
UE4Editor_Landscape!ALandscapeProxy::CreateLandscapeInfo() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\landscape\private\landscape.cpp:718]
UE4Editor_Landscape!ALandscapeProxy::PostRegisterAllComponents() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\landscape\private\landscape.cpp:978]
UE4Editor_Engine!AActor::IncrementalRegisterComponents() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\engine\private\actor.cpp:4016]
UE4Editor_Engine!ULevel::IncrementalUpdateComponents() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\engine\private\level.cpp:875]
UE4Editor_Engine!UWorld::AddToWorld() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\engine\private\world.cpp:1905]
UE4Editor_Engine!UWorld::UpdateLevelStreamingInner() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\engine\private\world.cpp:2521]
UE4Editor_Engine!UWorld::UpdateLevelStreaming() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\engine\private\world.cpp:2582]
UE4Editor_Engine!UWorld::FlushLevelStreaming() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\engine\private\world.cpp:2611]
UE4Editor_Engine!UWorld::RefreshStreamingLevels() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\engine\private\levelactor.cpp:1233]
UE4Editor_UnrealEd!EditorLevelUtils::AddLevelToWorld() [d:\build\++ue4+release-4.13+compile\sync\engine\source\editor\unrealed\private\editorlevelutils.cpp:217]
UE4Editor_UnrealEd!EditorLevelUtils::AddLevelsToWorld() [d:\build\++ue4+release-4.13+compile\sync\engine\source\editor\unrealed\private\editorlevelutils.cpp:153]
UE4Editor_WorldBrowser!FStreamingLevelCollectionModel::HandleAddExistingLevelSelected() [d:\build\++ue4+release-4.13+compile\sync\engine\source\editor\worldbrowser\private\streaminglevels\streaminglevelcollectionmodel.cpp:504]
UE4Editor_WorldBrowser!TBaseSPMethodDelegateInstance<0,FStreamingLevelCollectionModel,0,TTypeWrapper<void> __cdecl(TArray<FAssetData,FDefaultAllocator> const & __ptr64),bool>::Execute() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\public\delegates\delegateinstancesimpl.h:317]
UE4Editor_WorldBrowser!TBaseSPMethodDelegateInstance<0,FStreamingLevelCollectionModel,0,void __cdecl(TArray<FAssetData,FDefaultAllocator> const & __ptr64),bool>::ExecuteIfSafe() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\public\delegates\delegateinstancesimpl.h:424]
UE4Editor_UnrealEd!`FEditorFileUtils::OpenLevelPickingDialog'::`2'::FLocal::OnLevelsSelected() [d:\build\++ue4+release-4.13+compile\sync\engine\source\editor\unrealed\private\filehelpers.cpp:1825]
UE4Editor_UnrealEd!TBaseStaticDelegateInstance<void __cdecl(TArray<FAssetData,FDefaultAllocator> const & __ptr64),TBaseDelegate<void,TArray<FAssetData,FDefaultAllocator> const & __ptr64> >::ExecuteIfSafe() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\public\delegates\delegateinstancesimpl.h:1017]
UE4Editor_ContentBrowser!SAssetDialog::OnConfirmClicked() [d:\build\++ue4+release-4.13+compile\sync\engine\source\editor\contentbrowser\private\sassetdialog.cpp:360]
UE4Editor_ContentBrowser!TMemberFunctionCaller<SAssetDialog,FReply (__cdecl SAssetDialog::*)(void) __ptr64>::operator()<>() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\public\delegates\delegateinstanceinterface.h:161]
UE4Editor_ContentBrowser!TTupleImpl<TIntegerSequence<unsigned int> >::ApplyAfter<TMemberFunctionCaller<SAssetDialog,FReply (__cdecl SAssetDialog::*)(void) __ptr64> >() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\public\delegates\tuple.h:115]
UE4Editor_ContentBrowser!TBaseSPMethodDelegateInstance<0,SAssetDialog,0,FReply __cdecl(void)>::Execute() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\public\delegates\delegateinstancesimpl.h:317]
UE4Editor_Slate!TBaseDelegate<FReply>::Execute() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\public\delegates\delegatesignatureimpl.inl:521]
UE4Editor_Slate!SButton::OnMouseButtonUp() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\slate\private\widgets\input\sbutton.cpp:278]
UE4Editor_Slate!<lambda_8d0e9a1da76abd0a756a3a9d775f5ed1>::operator()() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:4901]
UE4Editor_Slate!FEventRouter::Route<FReply,FEventRouter::FToLeafmostPolicy,FPointerEvent,<lambda_8d0e9a1da76abd0a756a3a9d775f5ed1> >() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:215]
UE4Editor_Slate!FSlateApplication::RoutePointerUpEvent() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:4890]
UE4Editor_Slate!FSlateApplication::ProcessMouseButtonUpEvent() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:5348]
UE4Editor_Slate!FSlateApplication::OnMouseUp() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:5328]
UE4Editor_Core!FWindowsApplication::ProcessDeferredMessage() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:1584]
UE4Editor_Core!FWindowsApplication::DeferMessage() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:1930]
UE4Editor_Core!FWindowsApplication::ProcessMessage() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:747]
UE4Editor_Core!FWindowsApplication::AppWndProc() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:669]
user32
user32
UE4Editor_Core!FWindowsPlatformMisc::PumpMessages() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\private\windows\windowsplatformmisc.cpp:905]
UE4Editor!FEngineLoop::Tick() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\launch\private\launchengineloop.cpp:2788]
UE4Editor!GuardedMain() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\launch\private\launch.cpp:156]
UE4Editor!GuardedMainWrapper() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:126]
UE4Editor!WinMain() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:202]
UE4Editor!__scrt_common_main_seh() [f:\dd\vctools\crt\vcstartup\src\startup\exe_common.inl:264]
kernel32
ntdll