When trying to convert a non-WP map with OnlyMergeSubLevels enabled crash after a while
1. Create and open a new non-WP map
2. Add a landscape and save it
3. Select [Tools]->[Convert Levels...] from the editor
4. Select the map from Step1 and convert with only OnlyMergeSubLevels enabled
Crash after a while
LogWindows: Error: appError called: Assertion failed: !LandscapeProxy || LandscapeProxy->GetGridSize() == Landscape->GetGridSize() [File:D:\Github\Release-5.3\Engine\Source\Runtime\Landscape\Private\LandscapeConfigHelper.cpp] [Line: 86] LogWindows: Error: Windows GetLastError: ?n?g?h???a?3?o?A?E?B (6) LogWindows: Error: === Critical error: === LogWindows: Error: LogWindows: Error: Assertion failed: !LandscapeProxy || LandscapeProxy->GetGridSize() == Landscape->GetGridSize() [File:D:\Github\Release-5.3\Engine\Source\Runtime\Landscape\Private\LandscapeConfigHelper.cpp] [Line: 86] LogWindows: Error: LogWindows: Error: LogWindows: Error: LogWindows: Error: [Callstack] 0x00007ffbbbd6d8a1 UnrealEditor-Landscape.dll!`FLandscapeConfigHelper::ChangeGridSize'::`2'::<lambda_2>::operator()() [D:\Github\Release-5.3\Engine\Source\Runtime\Landscape\Private\LandscapeConfigHelper.cpp:157] LogWindows: Error: [Callstack] 0x00007ffba59e24ea UnrealEditor-Engine.dll!FActorPartitionGridHelper::ForEachIntersectingCell() [D:\Github\Release-5.3\Engine\Source\Runtime\Engine\Private\ActorPartition\ActorPartitionSubsystem.cpp:80] LogWindows: Error: [Callstack] 0x00007ffbbbd7a29e UnrealEditor-Landscape.dll!FLandscapeConfigHelper::ChangeGridSize() [D:\Github\Release-5.3\Engine\Source\Runtime\Landscape\Private\LandscapeConfigHelper.cpp:223] LogWindows: Error: [Callstack] 0x00007ffbb624fe64 UnrealEditor-UnrealEd.dll!`UWorldPartitionConvertCommandlet::Main'::`2'::<lambda_7>::operator()() [D:\Github\Release-5.3\Engine\Source\Editor\UnrealEd\Private\Commandlets\WorldPartitionConvertCommandlet.cpp:1029] LogWindows: Error: [Callstack] 0x00007ffbb62515af UnrealEditor-UnrealEd.dll!`UWorldPartitionConvertCommandlet::Main'::`2'::<lambda_9>::operator()() [D:\Github\Release-5.3\Engine\Source\Editor\UnrealEd\Private\Commandlets\WorldPartitionConvertCommandlet.cpp:1167] LogWindows: Error: [Callstack] 0x00007ffbb6299f4e UnrealEditor-UnrealEd.dll!UWorldPartitionConvertCommandlet::Main() [D:\Github\Release-5.3\Engine\Source\Editor\UnrealEd\Private\Commandlets\WorldPartitionConvertCommandlet.cpp:1209] LogWindows: Error: [Callstack] 0x00007ff732ca6933 UnrealEditor.exe!FEngineLoop::PreInitPostStartupScreen() [D:\Github\Release-5.3\Engine\Source\Runtime\Launch\Private\LaunchEngineLoop.cpp:4135] LogWindows: Error: [Callstack] 0x00007ff732c9c6e6 UnrealEditor.exe!GuardedMain() [D:\Github\Release-5.3\Engine\Source\Runtime\Launch\Private\Launch.cpp:140] LogWindows: Error: [Callstack] 0x00007ff732c9caaa UnrealEditor.exe!GuardedMainWrapper() [D:\Github\Release-5.3\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:118] LogWindows: Error: [Callstack] 0x00007ff732c9ff84 UnrealEditor.exe!LaunchWindowsStartup() [D:\Github\Release-5.3\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:258] LogWindows: Error: [Callstack] 0x00007ff732cb5ef4 UnrealEditor.exe!WinMain() [D:\Github\Release-5.3\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:298] LogWindows: Error: [Callstack] 0x00007ff732cb92ea UnrealEditor.exe!__scrt_common_main_seh() [D:\a\_work\1\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288] LogWindows: Error: [Callstack] 0x00007ffc22227614 KERNEL32.DLL!UnknownFunction [] LogWindows: Error:
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-190821 in the post.