Deferring Blueprint CDO construction at load time is leading to some data loss.

UE - Gameplay - Blueprint - Jan 27, 2023

Various licensees are reporting data loss on load due to the change that was made for [Link Removed] in which we now defer Blueprint CDO construction on load until the finalization phase. This issu ...

Inconsistent ListView entry sizes can prevent the ListView from being scrolled to the bottom

UE - Editor - UI Systems - Slate - May 4, 2022

Since the contents of a ListView are virtualized, the ListView estimates the size of the scroll box's contents based on the on-screen elements. This can lead to some situations where DistanceFromBot ...

Blueprint Launches onto tvOS fail during runstep: Error_DeviceOSNewerThanSDK

UE - Platform - Mobile - Apr 19, 2019

When a user launches blueprint project to a tvOS device they will fail to run the project during the run step and if they manually try to launch the app from the dashboard. This issue does not repr ...

Changing the scale of a single HISM instance greatly affects the LOD selection of all instances

UE - Rendering Architecture - Sep 22, 2025

When using ISMs and HISMs, each instance can have its own transform, which can affect the LOD selection of one or more instances. For HISMs in particular, changing the scale of a single instance gre ...

Always Relevant actor may replicate incorrect movement mode when the walkable floor becomes irrelevant

UE - Gameplay - Player Movement - Feb 26, 2024

When the character class is set to always relevant, if a client travels very far away from another character, such that the character is relevant but the component they're standing on is not (but al ...

Composite font uses a sub-font, even when the sub-font doesn't support the character

Tools - Apr 7, 2016

I have a fix for this shelved in CL# 2937344, so it would be good to get it into 4.12 once the user verifies the fix. ...

MotionWarping does not recognize new MontageInstance with the same montage

UE - Anim - Gameplay - Jan 11, 2023

When the same AnimMonotage is played again while moving with MotionWarping & RootMotion, UAnimNotifyState_MotionWarping does not recognize it. From licensee: The issue was that in URootMotionMod ...

tvOS/IOS: Fails to Build with dSYM Options Enabled Due to DsymExporter Erroring Out

UE - Platform - Mobile - Jan 22, 2019

When attempting to package for tvOS or iOS with the generate dSYM options enabled, numerous instances of the following errors occur:[2019.01.21-20.53.35:739][138]UATHelper: Packaging (tvOS): [2019 ...

UAssetManager::ChangeBundleStateForPrimaryAssets: Performance: Avoid canceling loads in progress when new bundles added and the in progress bundles are kept

UE - Foundation - Data Pipeline - Cooker - Mar 4, 2024

UAssetManager::ChangeBundleStateForPrimaryAssets allows adding new BundleNames to the list of BundleNames loaded for a PrimaryAssetId. Each BundleName specifies a BundleEntry with a list of assets. ...

NPC - Instances does not get updates from changes to the parent Niagara Parameter Collection in the editor

UE - Niagara - Oct 4, 2024

When an Niagara Parameter Collection (NPC) is selected as the parent Collection for an NPC Instance (NPCI), all of its current parameters are carried over to the NPCI with their current values as th ...