Editor crashes when actors using child actor component are loaded while Static mesh actor filter is enabled in the outliner

UE - Editor - Dec 5, 2022

Reproduced 3/3 times. Unclear whether this is a regression as filter GUI is new in 5.1 for Outliner. ...

Behavior Trees cannot be saved if the Blackboard assigned to it was opened before opening the Behavior Tree from the Content Browser

UE - AI - Nov 2, 2015

Behavior Trees cannot be saved if the Blackboard assigned to it was opened before opening the Behavior Tree from the Content Browser. Reproduced in 4.8.3 binary, 4.9.2 binary, 4.10 Preview 3 binary ...

Volumetric Translucent Shadows will only work if you select the mesh, doesn't show up in game

UE - Graphics Features - Aug 18, 2015

When using Volumetric Translucent Shadows for static meshes the shadows will only work if the mesh is selected. When the mesh is deselected it will not render. This worked in 4.8.3, but is broken ...

GAS: Ability that destroys owning actor on activate causes crashes due to ABILITYLIST_SCOPE_LOCK

UE - Gameplay - Gameplay Ability System - Oct 31, 2023

A GameplayAbility that destroys its owning actor inside ActivateAbility() causes a crash, because actor destruction will modify the ability list but ActivateAbility() is called within an ABILITYLIST ...

Random Stream variables in the GameMode are reset every PIE

UE - Gameplay - Blueprint - Jul 6, 2015

Random Stream variables in the GameMode are reset every PIE. Workaround is to use Set Random Stream Seed before using the Stream value. Reproduced in 4.7.6, 4.8.1, and Main (//depot/UE4/Promotable ...

When the Initial Position of an Animation Asset is entered outside the expected range, the animation gets stucked and does not refresh.

UE - Runtime - Animation - Mar 18, 2024

The animation gets "corrupted" when the Initial Position value has an invaildad value. In this case, this means that the Initial Position value is outside the range of the duration of the Animation. ...

TSR and TAA history accumulation gets reset when taking viewport screenshots or when clicking outside the tree in the outliner

UE - Rendering - Features - May 30, 2025

TSR (and TAA) history accumulation gets reset when taking viewport screenshots or when clicking on an empty area in the outliner (when a tree item is selected). This can cause an undesirable issue w ...

Switch on custom enum causes compilation errors after Hot Reload

UE - Foundation - Core - Sep 28, 2015

If the project is hot reloaded while a Switch on Enum is inside of a blueprint which is switching on a custom enum, the switch will become corrupted. It changes the 'selection' pin to take a Byte pa ...

'Get Distance Along Spline At Spline Point' Causes Crash

Tools - Jul 28, 2018

User reports that the reason for the crash is that because UpdateSpline is false on the AddSplinePointAtIndex blueprint node, this line is never called [ReparamTable.Points.Reset(NumSegments * Repar ...

Mac - Inconsistent results for Lumen renders

TM - Rendering - Jun 3, 2025

Reported in SF [Link Removed] and [Link Removed] Users on Mac are reporting inconsistent rendering results for Lumen in image exports that do not include any settings changes. When exporting some ...