This is a common and longstanding crash that has affected more than 300 users since 4.12.
The callstack is closely similar to [Link Removed], although with different error messages.
User Descriptions
Source Context
457 if (FramesRecorded < FramesToRecord) 458 { 459 const FBlendedHeapCurve& AnimCurves = Component->GetAnimationCurves(); 460 461 check(SpaceBases.Num() == PreviousSpacesBases.Num()); 462 463 ***** TArray<FTransform> BlendedSpaceBases; 464 BlendedSpaceBases.AddZeroed(SpaceBases.Num()); 465 466 UE_LOG(LogAnimation, Log, TEXT("DeltaTime : %0.2f, Current Frame Count : %d, Frames To Record : %d, TimePassed : %0.2f"), DeltaTime 467 , FramesRecorded, FramesToRecord, TimePassed); 468
RESULT
Crash
Assertion failed: SpaceBases.Num() == PreviousSpacesBases.Num() [File:D:\Build\++UE4+Release-4.17+Compile\Sync\Engine\Source\Editor\SequenceRecorder\Private\AnimationRecorder.cpp] [Line: 462] UE4Editor_SequenceRecorder!FAnimationRecorder::UpdateRecord() [animationrecorder.cpp:464] UE4Editor_SequenceRecorder!FAnimRecorderInstance::Update() [animationrecorder.cpp:819] UE4Editor_SequenceRecorder!FAnimationRecorderManager::Tick() [animationrecorder.cpp:715] UE4Editor_SequenceRecorder!FSequenceRecorder::Tick() [sequencerecorder.cpp:257] UE4Editor_SequenceRecorder!FSequenceRecorderModule::TickSequenceRecorder() [sequencerecordermodule.cpp:603] UE4Editor_SequenceRecorder!TBaseStaticDelegateInstance<void __cdecl() [delegateinstancesimpl.h:1027] UE4Editor_Engine!TBaseMulticastDelegate<void,float>::Broadcast() [delegatesignatureimpl.inl:937] UE4Editor_UnrealEd!UEditorEngine::Tick() [editorengine.cpp:1915] UE4Editor_UnrealEd!UUnrealEdEngine::Tick() [unrealedengine.cpp:402] UE4Editor!FEngineLoop::Tick() [launchengineloop.cpp:3215] UE4Editor!GuardedMain() [launch.cpp:166] UE4Editor!GuardedMainWrapper() [launchwindows.cpp:134] UE4Editor!WinMain() [launchwindows.cpp:210] UE4Editor!__scrt_common_main_seh() [exe_common.inl:253] kernel32!BaseThreadInitThunk() ntdll!RtlUserThreadStart()
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-49778 in the post.