"Assertion failed" trying to edit UInstancedStaticMesh created in C++ in Editor

I extend AActor in C++ and create a property of type TSubobjectPtr<UInstancedStaticMeshComponent> like this:

Thing.h

UPROPERTY(VisibleAnywhere, EditInline, Category = MyCategory)
TSubobjectPtr<UInstancedStaticMeshComponent> MyISM;

I then do the following

Thing.cpp

AThing::AThing(const class FPostConstructInitializeProperties& PCIP)
	: Super(PCIP)
{
	TSubobjectPtr<USphereComponent> DummyComp = PCIP.CreateDefaultSubobject<USphereComponent>(this, TEXT("SphereComp"));
	DummyComp->InitSphereRadius(1.0f);
	RootComponent = DummyComp;

	MyISM = PCIP.CreateDefaultSubobject<UInstancedStaticMeshComponent>(this, TEXT("MyISM"));
	MyISM->AttachParent = RootComponent;
	MyISM->SetMobility(EComponentMobility::Static);
}

I then extend the Class in a Blueprint, place the blueprint in the level, and when I try to edit the “Instance Start Culling” value in the “Details” pane, I get

ErrorString 0x000000000066c440 L"Assertion failed: !EditReregisterContexts.Find(this)" wchar_t[4096]

May be a duplicate of

Hi ,

Thank you for the information that you provided. I was able to reproduce the issue that you described, and I have submitted a ticket for it to be investigated further.