ACineCameraAttachMount's "Target Actor" constraint does not work with Spawnables or Replaceables in Sequencer

UE - Virtual Production - Tools - Virtual Camera - Aug 12, 2025

Constraints (UTickableConstraint) are usually created throuh the "Animation" tab available in the Editor's "Animation Mode". When created through that interface while Sequencer is open, the internal ...

Bug in StringTemplate.cpp related to modulo operator in MaterialTemplate.ush (code fix provided)

UE - Rendering Architecture - Materials - Jun 25, 2024

Shader Template files like MaterialTemplate.ush do not submit previous chunks when encountering a `%` character, unless that `%` character is `%s` or `% {...} `. Because the error is happening ...

check(!bPostTickComponentUpdate) fails triggered by ~FStaticMeshComponentBulkReregisterContext() and FD3D12DynamicRHI::ProcessInterruptQueueUntil()

UE - Gameplay - Components - Jul 23, 2024

Context: Some ActorComponents can schedule end-of-frame work which UWorld executes later in the frame in UWorld::SendAllEndOfFrameUpdates(). By-design it appears that it's not allowed to schedule mo ...

Linux crash upon opening maps in Soul: City content pack

UE - Graphics Features - Jan 29, 2018

Opening the maps from the Soul: City asset pack on Linux causes a crash. This seems to be rendering related. It was originally reported as a Vulkan specific issue but we've reproduced it without Vul ...

Unable to change Actor Coloration View Modes in PIE

UE - World Creation - Worldbuilding Tools - Jul 20, 2025

When in PIE changing Actor Coloration view modes from the viewport visualisation mode [Liit] -> [Actor Coloration] -> ... Does not update correctly when switching view mode and sometimes isn't corr ...

When playing matinee, scrubbing can cause sound to keep playing when it isn't triggered

UE - Audio - May 31, 2016

When playing matinee, scrubbing can cause sound to keep playing when it isn't triggered Note: This was entered as a bug to re-work the fix from the pull request found here: [Link Removed] ...

Collision Channel on Particle Systems not saving

UE - Graphics Features - Oct 21, 2014

Setting the Collision Channel to anything other than World Static will reset on closing and restarting the editor. ...

FIOSInputInterface::SendControllerEvents crash due to UIInterfaceOrientation call from game thread

UE - Platform - Mobile - Apr 29, 2020

From [Link Removed], licensee reports We believe that querying the UIInterfaceOrientation via UIApplication on the game thread is the issue here. We have made changes to IOSInputInterface.cpp and I ...

VS2015 Update 3 prevents the editor from compiling code

UE - Foundation - Cpp Tools - UnrealBuildTool - Jun 28, 2016

Updating Visual Studio 2015 to Update 3 prevents code projects from compiling / creating new code projects ...

Certain UPROPERTY values are not updated during auto-recompile

UE - Gameplay - Blueprint - Aug 4, 2016

Sometimes manual recompile is required to make a blueprint actually recompile data-only changes, but not always. If the last manual compile was with default values, then changes are not updated. If ...