AnimNotify serialization crash in editor

UE - Runtime - Animation - Mar 15, 2026

The crash is caused by changing the variable type of an AnimNotify that is already referenced by a montage. This issue cannot be reproduced in 5.6. ...

MotionWarping does not recognize new MontageInstance with the same montage

UE - MVF Character - Animation - 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 ...

Camera Component - Regression in Unreal 5.7+

UE - QA - Support - Oct 4, 2026

POST BODY:Summary Hey there - I’ve been sticking with Unreal Engine 5.6 for cinematics because of a regression that's been made to CineCameraActors (specifically the CameraComponent nested inside of ...

[CrashReport] Access violation - FLandscapeEditDataInterface::SetAlphaData()

UE - LD & Modeling - Terrain - Landscape - Jul 19, 2017

This is a common crash affecting users in 4.15 and 4.16. This callstack was previously linked to [Link Removed], but that had a specific repro case that was fixed in 4.14. Users are not providing ...

Changing a Media Player asset from Stream Mode: FromURL to From Memory crashes the editor

Tools - Dec 30, 2014

Changing a Media Player asset from Stream Mode: FromURL to From Memory crashes the editor. In 4.8, the editor crashes immediately upon changing that value, with no crash report. In 4.6 and 4.7 Pre ...

Assigning a static mesh to a Mutable Clip Mesh With Mesh Node can crash the editor

UE - Runtime - Mutable - Jul 4, 2025

Context: The Mutable plugin has a modifier node called Clip Mesh With Mesh that allows Static Mesh modifiers to be assigned as the clip mesh. Under certain circumstances, an assert can be triggered ...

Crash when quick binding a function in a class that extends LevelSequenceDirector

UE - Anim - Sequencer - Sep 16, 2020

The purpose was to create a Level Sequence Director inheritance class so that the same event could be reused in multiple sequencers. Attempting to quick-bind this base Level Sequence Director event ...

Open Formats: Import - Issue with importing alembic files: the skeletal mesh asset doesn't contain LOD description

UE - VEI - Open File Formats - Sep 15, 2026

Helloo everyone!! 😄 We are experiencing an issue with importing skeletal meshes from alembic. For reference, this issue happens in vanilla engine 5.7.4, but it doesn't occur in versions 5.6.x. 1) ...

If using SetAlignmentInViewport in Construct, the value with it is ignored

UE - AI Workflows - UI Systems - UMG - Jan 27, 2023

If SetAlignmentInViewport is called in the UMG Construct, it is ignored internally. This is due to a change that came in 5.1, so it worked fine in 5.0. First, when the Set Alignment in Viewport nod ...

Open Formats: Interchange Import Runtime - Interchange ImportAssetAsync runtime GLB import — materials, textures, tangents, and shaders non-functional in packaged builds (6 issues, UE 5.7.4)

UE - VEI - Open File Formats - Apr 30, 2026

Description* We are using Interchange's `UInterchangeManager::ImportAssetAsync()` to import GLB files at runtime in a packaged (Shipping) application. The orchestration layer (`ImportInternal` in `In ...