Crash on adding new element to ChaosCacheCollection if ChaosCacheCollection is open in editor

UE - Simulation - Physics - Destruction - Dec 11, 2020

More ways to reproduce:In Chaos Cache Collection Editor press Add Element button (no matter when you will do this step)If in Step13 from Steps to reproduce you won't place Chaos Cache Collection Edi ...

ChaosCacheManager is not reproducing Collision Events the second time you Record and Play

UE - Simulation - Physics - Mar 28, 2025

ChaosCacheManager (CCM) is not reproducing Collision events the second time (and onwards) we record a Geometry Collection (GC) breaking session. Particles set to track Collision Events correctly fol ...

Hot Reload does not update blueprint pins

UE - Gameplay - Blueprint - Jan 15, 2015

When changing the variable type or return type of a function in code and hot reload in the editor, blueprints that use the variable/function do not have their pins updated until the editor is closed ...

ShadowProject gpu performance regression from Aftermath

UE - Graphics Features - May 9, 2017

The issue was originally noticed between 4.15.1 and 4.16 Preview, but now appears to have regressed between 4.15.1 and 4.15.2. ...

CLONE - ShadowProject gpu performance regression from Aftermath

UE - Graphics Features - May 19, 2017

The issue was originally noticed between 4.15.1 and 4.16 Preview, but now appears to have regressed between 4.15.1 and 4.15.2. ...

Crash after creating a suboject for RootComponent if the actor is placed on the level

UE - Foundation - Cpp Tools - Hot Reload - Nov 6, 2020

The crash occurs when trying to assign a new value to RootComponent if the Pawn is already placed on the level Crash does not happen in  P4 //UE4/Release-4.25.3 CL 13942748 Other steps to reproduc ...

Compiling on Mac fails if build path has spaces

UE - Platform - Apple - Jan 6, 2015

UPDATE: We were able to get around this issue by renaming our external drives. The actual problem is that Mono's xbuild fails to build UnrealBuildTool QA REGRESSION: YesWORKING: 2386770BROKEN: 23 ...

No Dynamic Shadows on Translucent Materials in iOS Preview

UE - Platform - Mobile - Jul 23, 2018

There are no dynamic shadows on translucent materials in the "iOS Preview" for the preview rendering level. Working as intended in 4.16 CL# 3561208, 4.17 CL# 3658906, and 4.18 CL# 3832480. Found i ...

Templated enum GetValueAsString function returns incorrectly formatted string

UE - CoreTech - Aug 19, 2020

For many years there has been a static function on UEnum called GetValueAsString which would convert an enum like EAttachmentRule::KeepWorld to the string "KeepWorld", if you passed in the explicit ...

[CrashReport] UE4Editor_UnrealEd!TArray<TScriptDelegate<FWeakObjectPtr>,FDefaultAllocator>::Find() [array.h:784]

UE - Gameplay - Aug 22, 2017

This is a regular crash occurring in 4.17. It may be a regression as there is no immediate evidence of it occurring in prior releases. Users have not provided any descriptions of their actions whe ...