UMG: RetainerBox with zero-size child returns incorrect LayerId on OnPaint()

UE - Editor - UI Systems - Nov 4, 2025

When a RetainerBox contains a child that for some reason has a desired size of zero, its OnPaint() method can incorrectly return LayerId 0. Afterwards, widgets further down the hierarchy can base th ...

Client crashes after second seamless travel when a blueprint manually placed in the world spawns a replicated actor

UE - Networking - Sep 19, 2019

When a user loads into a level that spawns replicated actors using manually placed blueprints twice using ServerTravel with Seamless Travel enabled it will crash. It looks like the engine can't find ...

Material expression If node has been broken, major regression that shipped in 4.6

UE - Graphics Features - Dec 9, 2014

This sounds legit. Anyone mess with the if node recently? There seems to be a regression where existing content is broken. This should be fixed ASAP and patched into 4.6. https://forums.unrealen ...

[CrashReport] UE4Editor_MaterialEditor!CastChecked<UMaterialGraphNode,UEdGraphNode>() [casts.h:192]

UE - Rendering Architecture - Materials - Aug 31, 2016

This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Descriptions from users are provided below. Error message: Access violation - code c0000005 ( ...

[CrashReport] UE4Editor_Core!FArchive::SerializeCompressed() [archive.cpp:447]

UE - Foundation - Core - Nov 17, 2016

This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Error message: Assertion failed: PackageFileTag.CompressedSize == PACKAGE_FILE_TAG_SWAPPED [L ...

Calling UBlueprintMapLibrary::GenericMap_Find with a non-existent key causes a memory leak

UE - Framework - Blueprint - Apr 15, 2025

When Calling UBlueprintMapLibrary::GenericMap_Find with a non-existent key, the function construct the default structure in-place on the given pointer without destroying the object. This behavior ca ...

Editing an instanced variable that is nested in two other instanced variables causes a crash

UE - Gameplay - Blueprint - Jul 2, 2015

If a user edits a instanced variable which is nested inside two other instanced variables in blueprint editor, a crash will occur ...

Animating blueprint mesh duplicates uncontrollably

UE - Gameplay - Components - Apr 15, 2015

When animating within a blueprint of a subclass created in c++, the animating mesh replicates itself uncontrollably. Added to .h: UPROPERTY() UBoxComponent* BoxComp; UPROPERTY() USkeletalMeshCompo ...

Enum Meta is being ignored when project is packaged

Tools - Nov 4, 2014

When using UMeta on Enums, text is ignored when doing Enum to String on a packaged project. ...

macOS build appears to hang due to UBT deadlocking on ps buffer

UE - Foundation - Cpp Tools - Apr 22, 2021

Licensee reports buffer deadlock issue in System/BuildHostPlatform.cs (lines 283-329). Moving Proc.WaitForExit() to after the for-loop seems to resolve the issue for them.publicoverride ProcessInf ...