Movable point light disappeared by MinScreenRadiusForLights and appeared back looks deemed.

UE - Platform - Mobile - Jun 25, 2021

The movable point light is abnormally lit when it disappeared by the setting of r.MinScreenRadiusForLights rather than "Max draw distance" and appears back. After you disable and enable the "Affect ...

Creating a function with parameter type TEnumAsByte<MyEnum> will crash while compiling

UE - Editor - Workflow Systems - Jan 11, 2022

This is a regression.This does not affect UE5. Creating a function with parameter type TEnumAsByte<MyEnum> will crash while compiling. In 4.26 and UE5 the code compiles without issue, and the user ...

MemReport does not seem to respect mesh streaming

UE - Rendering Architecture - Aug 6, 2024

The function "FStaticMeshLODResources::GetResourceSizeEx(...)" does not take into account that the buffers might be emptied, due to Mesh Streaming. This causes "obj list" to report sizes larger than ...

[AI] Area Class to Replace does not work on SplineNavModifierComponent

UE - AI - Navigation - Jun 16, 2025

The SplineNavModifierComponent does not have the same behavior as regular nav modifier components where the modifier can specify that it only replaces a given NavArea class. Setting the area class t ...

Crash w. 'Serialized Class LinkerPlaceholderExportObject for a property of BlueprintGeneratedClass'

UE - Gameplay - Blueprint - Sep 25, 2017

I was attempting to repro [Link Removed]. I created a new Actor BP, placed it in the level, added a ref to it to the level BP (instead of the projectile approach in the repro), and tried to save my ...

Ensure condition failed / Crash on BP Compile after adding variable

UE - Gameplay - Blueprint Compiler - Jan 26, 2018

Crash when compiling BP (containing user defined struct + object reference) after adding variable. ...

Changing particle system template via Blueprints crashes Editor and packaged game

UE - Niagara - Apr 4, 2019

Setting a ParticleSystem component in a Blueprint to none/null with a "Set Template" node causes the editor and the packaged project to crash. I have noticed this when migrating my game to 4.22, whi ...

D3D HUNG crash - FD3D11DynamicRHI::RHIReadSurfaceFloatData()

UE - Graphics Features - Jan 18, 2017

This is one of the widespread D3D Hung crashes that have existed since 4.14. This particular callstack has affected around 300 users. The issue has been successfully reproduced on a home PC. Dxdi ...

Text block Outline cropped out at large sizes

UE - Editor - UI Systems - Mar 8, 2017

Text block Outline cropped out at large sizes. This affects Grid Panels and was additionally tested with Horizontal boxes with the same result Regression: This issue does not occur in 4.14.3 Binary ...

Per-section shadow/collision flags lost when merging actors

OLD - Anim - Mar 24, 2017

Information loss when merging actors such as cast shadow and collision. If one of the actors being merged has a different setting such as not casting shadows. This information will be lost and repla ...