In -game in Editor, if streaming-in a LevelInstance and initialize its world partition, then leaving that cell and make it go outside the streaming grid, to re-enter it again, will trigger a check(!StreamingPolicy) if no GC has happened during that time.

UE - World Creation - Worldbuilding Tools - World Partition - Jan 27, 2025

This crash can be fixed by adding a couple of || IsRunningGame() like it is done here:    FGenerateStreamingContext Context = FGenerateStreamingContext()        .SetLevelPackagesToGenerate((bIsPIE ...

Iris - Ensure in MarkObjectDirty when calling multicast from component owned by bOnlyRelevantToOwner actor

UE - Networking - Iris - Sep 24, 2024

It seems as though the component is in scope for more than one connection, despite its owner only being relevant to one. Enabling Net.Iris.Filtering.ValidateNobSubObjectInScopeWithFilteredOutRootObj ...

[AI] Destroying an actor while using pooled actors with MassActorSpawnerSubsystem causes a nullptr exception crash

UE - AI - Mass - Mar 19, 2023

If an actor that is used in the pooled actor list of UMassActorSpawnerSubsystem is destroyed, it causes a nullptr exception in UMassActorSpawnerSubsystem::SpawnOrRetrieveFromPool. The subsystem atte ...

Modifying FinstancedStruct (Blueprint structs) properties inside another FInstancedStruct triggers an ensure and properties do not get saved.

UE - AI - Dec 16, 2024

There is a bug with Blueprint structs having FInstancedStruct as a property. If you modify the DefaultValues of any property of an FInstancedStruct inside the blueprint struct asset, an ensure will ...

Nested PackedLevel in Duplicated LevelInstance check failure

UE - World Creation - Worldbuilding Tools - Level Instances - Oct 13, 2022

Assert in EditorEngine.cpp after HotReload

UE - Foundation - Core - Jan 27, 2017

This occurred when I tried to repro an ensure and crash the resulted in [Link Removed]. In the crash group on the Crashreport website I noticed that KimK had the same callstack as this one. She wrot ...

Modifying ShooterGame header file for faster compiling causes crash behavior.

UE - Foundation - Core - Jan 11, 2019

Using bFasterWithoutUnity and MinFilesUsingPrecompiledHeaderOverride, on ShooterGame.Build.Cs results in Engine crash. ...

Crash: Corrupt asset/map data is no longer correctly detected and handled

UE - Foundation - Core - Oct 27, 2016

Corrupted data was previously handled gracefully without crashing, but in 4x14 the same data crashes the editor. ...

LevelSequence Editor consumes input, even if the user last focused the Level Viewport

UE - Anim - Sequencer - Nov 27, 2024

LevelSequenceEditor has input priority over the Level viewport and other editor modules even though the Level viewport has been the last one selected. An example would be a cut operation. If you ha ...

Editor crashes on user project when attempting to spawn an actor from a struct within user's project.

UE - Networking - Sep 23, 2015

Editor crashes when attempting to spawn an actor from a struct within user's project. Frequency: 5/5 crashreporter: [Link Removed] ...