Unreal Engine Issues
Unreal Engine Issues
Conflict between sequencer transform track and Parent Constraint from the Animation Mode breaks temporary pivot translation on any actor
UE - Anim - Anim in Engine - Jul 15, 2025Note: This affects all versions from at least UE 5.3, including mainline latest. The "Animation" Editor Mode allows creating constraints for level actors. One of these, the "Parent" constraint, con ...
Crash when manipulating Bone Space IK before setting EffectorSpaceBoneName
UE - Anim - Rigging - Feb 9, 2017Error message: Assertion failed: Pose.IsValidIndex(BoneIndex) [Link Removed] [Line: 528] Source Context: 513 const FTransform& ParentTransform = GetComponentSpaceTransform(ParentIndex); ...
Wrong WPO motion vectors due to Periodic World Space node
UE - Rendering - Graphics Features - May 13, 2026We've noticed smearing in grass due to wrong motion vectors. This appears to be caused by lack of previous frame support in the periodic world space node. This is how we fixed it: In MaterialTempl ...
FNotifyNodeInterface crashes when referenced Notify is invalid
UE - Anim - Runtime - Mar 1, 2024Currently FNotifyNodeInterface directly references notifies that live within the related anim sequence. This can cause intermittent crashes when notifies are removed as the UI can still reference t ...
Combined Translate and Rotate Mode broken when using Local Space
UE - Editor - Dec 22, 2023From UDN: When using the Combined Translate and Rotate Mode we run into an issue where the rotation arrow moves twice as fast as the coordinate frame. The object itself rotates correctly, but if we ...
Enable HDR Display Output on Game User Settings Crash
UE - Graphics Features - Jun 14, 2018Crash when attempting to enable HDR via UserSettings This crash will also occur when project is fullscreen. User's Environment: "I have an Nvidia GTX 1080 Ti and have two monitors attached: 1. ...
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 - Editor - Open File Formats - Apr 30, 2026Description* We are using Interchange's `UInterchangeManager::ImportAssetAsync()` to import GLB files at runtime in a packaged (Shipping) application. The orchestration layer (`ImportInternal` in `In ...
[CrashReport] UE4Editor_Slate!SMenuAnchor::SetIsOpen() [smenuanchor.cpp:372]
UE - Editor - UI Systems - Slate - Nov 2, 2017This is a trending crash coming out of the 4.18 release, and may be a regression. Users have not provided any descriptions of their actions when the crash occurred. Source Context 361 ...
For a TMap with C++ enum keys, deleting and re-adding a map entry in the Editor can corrupt the map data.
UE - Editor - Jul 19, 2024When adding an entry to a TMap using UE's property editors, in most cases the new entry comes with a default-initialized key (if such key already exists, the insertion fails). The case of a UENUM de ...
Changing the ComponentClass of a ACharacter twice and trying to set a SkeletalMeshAsset crashes the engine
UE - Anim - Jan 22, 2026Changing the ComponentClass of a ACharacter twice and trying to set a SkeletalMeshAsset crashes the engine with a "Cannot replace existing object of a different class" message. The conditions to re ...