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) ...

[CrashReport] UE4Editor_Engine!FShaderCompilingManager::LaunchWorker() [shadercompiler.cpp:1573]

UE - Graphics Features - Aug 21, 2017

This is a common and longstanding crash that has occurred since at least 4.9. The issue appears to be due to missing ShaderCompileWorker.exe in binaries, but many of these crashes occur in the vani ...

DataTable asset view runs out of (video) memory

UE - Editor - UI Systems - Slate - Feb 26, 2024

In some situation, Slate tries to secure incredible amount size data and run out of memory. This happens a cell having very long and complex serialized text appears on the editor and it is placed to ...

Conflict between sequencer transform track and Parent Constraint from the Animation Mode breaks temporary pivot translation on any actor

UE - Anim - Anim in Engine - Jul 15, 2025

Note: This affects all versions from at least UE 5.3, including mainline latest. The "Animation" Editor Mode allows creating constraints for level actors. One of these, the "Parent" constraint, con ...

Translucent materials in the PostMotionBlur pass can cause a flickering viewport artefact when using TAA

UE - Graphics Features - Feb 5, 2025

There appears to be a bug relating to rendering multiple windows that can trigger under unknown circumstances. It has been reported on rectangle lights in the forums and on PostMotionBlur materials ...

Crash rendering image sequence if the Sub-Level with matinee is not loaded

Tools - Apr 15, 2016

Crash rendering image sequence if the Sub-Level containing the matinee is not loaded. This seems to go away if the level is either set to "Always Loaded". Seems to be a result of people not switch ...

Editor crashes with 2 or more Clients when spawning in a Blueprint created from a Static Mesh using the Blueprint/Add Script button

UE - Networking - May 14, 2015

Editor crashes with 2 or more Clients when spawning a Blueprint created from a Static Mesh using the Blueprint/Add Script button. Blueprints created from Static Meshes using other methods do not cau ...

When breaking a level instance, foliage instances in the LevelInstance are placed in the wrong location

UE - World Creation - Worldbuilding Tools - Level Instances - Jul 8, 2023

Following code works as a work around. The code updates placement information of instances. TMap<UFoliageType*, TArray<const FFoliageInstancePlacementInfo*>> AInstancedFoliageActor::GetInstancesF ...

AddLocalTransform node does not match scale behavior described in the node's documentation

UE - Gameplay - Blueprint - Jun 29, 2018

The comment for the AddLocalTransform node states "Change in transform of the component in its local reference frame. Scale is unchanged." However, when the node is used, the existing scale of the o ...

Ensure breaking a link in anim blueprint Event Graph and then undoing

UE - Gameplay - Blueprint Editor - Jul 18, 2016

Ensure occurs when the user breaks a link in the animation blueprint's Event Graph and then undo's the action. I wasn't able to reproduce it in a class blueprint. ...