Crash when playing NiagaraSystem with mesh renderer in CPUSim with Compress Attributes enabled when stompmalloc is enabled

UE - Niagara - Jul 16, 2024

Crashes when playing Niagara particles with the following conditions enabled. It crashes only when stompmalloc is enabled, not when disabled. Enable Ray tracingEnable Compress Attributes in System P ...

Body Setup of a Static Mesh with Simple Collision will pass validation, but removing it and using only a Complex collision and setting Collision Complexity "Use Complex as Simple" will fail validation: "Bone None requires at least one collision shape".

UE - Simulation - Gameplay - Oct 20, 2025

Context: By default, Unreal Engine creates both simple and complex shapes, then, based on what the user wants (complex query versus simple query), the physics solver will use the corresponding shape ...

[CrashReport] UE4Editor_CoreUObject!StaticAllocateObject() [uobjectglobals.cpp:2153]

UE - Anim - Sequencer - Jun 3, 2016

Really close to the repro steps for [Link Removed] Same repro steps produced the following Buggs along with this one: [Link Removed] [Link Removed] Error message: Fatal error: [Link Removed] [Lin ...

When using Perforce, saving a level over another leaves the target umap file as "marked for delete"

UE - Editor - Workflow Systems - Mar 11, 2025

When working on a level asset and using command "File – Save Current Level As..." to save it over a different level asset, the engine first deletes the target level (that's going to be overwritten) ...

Variant Manager: LevelVariantSets asset corruption after rename or duplicate

UE - Editor - Content Pipeline - Oct 24, 2025

When renaming or duplicating a LevelVariantSets asset that contains a Director Blueprint, the internal DirectorClass reference becomes mismatched. Although the DirectorBlueprint pointer updates corr ...

Clicking the Add Variable button in a Struct that is referenced as two inputs in a function that is called in an Actor Blueprint's Construction Script causes a crash

UE - Gameplay - Blueprint - Jun 28, 2015

Clicking the Add Variable button in a Struct that is referenced as two inputs in a function that is called in an Actor Blueprint's Construction Script causes a crash. This does not occur in the Even ...

GAS: Mixed replication mode and error in MinimalReplicationTags code

UE - Gameplay - Gameplay Ability System - Apr 6, 2022

We're on 4.25.4. We recently turned on mixed mode replication for GAS, which seems to work fine and reduce bandwidth as expected. However one of our unit tests started failing with this error messag ...

iOS Show External Login UI Blueprint Node fails on new iOS devices

UE - Online - Jun 6, 2019

I have been trying to test iOS online subsystem functionality for my game and thought that this blueprint node was just broken. This bug will probably catch many UE4 developers that are new to iOS b ...

EnumRedirections from a Blueprint enum to a c++ enum does not redirect everything correctly.

UE - CoreTech - Aug 20, 2024

There is an engine bug when using the EnumRedirects feature inside a config file. If we have a Blueprint Enum used in our blueprints, and we want to convert all the Blueprint enum references to a C+ ...

Destructible mesh does not trigger overlap event for objects/pawns that are not moving

UE - Simulation - Physics - Destruction - Dec 12, 2014

DESCRIPTION: When using the generate overlap events for a destructible mesh with Static Mesh or skeletal mesh that is not moving will not generate an overlap event to be triggered. So long as the me ...