Unreal Engine Issues
Unreal Engine Issues
Overwriting an anim sequence may scale the play rate of the anim instead of modifying underlying frame rate
UE - CAPT - Tools - Take Recorder - Jul 21, 2026The frame rate for an anim sequence is not being changed as expected when its being overwritten / re-imported. ...
Crash in GC - FSharedStruct reachability race condition
UE - CoreTech - Jul 13, 2026This Jira was created from the linked EPS case: =============================================== This issue is caused by FSharedStruct batching reachability requests to the same underlying FInstan ...
Navigation data contained entirely within a Level Instance is not registered at runtime (PIE / standalone / packaged) in a World Partition persistent level
UE - AI - Navigation - Jul 13, 2026A licensee is composing independently-authored levels into a single World Partition persistent level by placing each as a Level Instance. NavMeshBoundsVolume / NavModifierVolume are placed inside ea ...
WorldPartition RuntimeHashSet: non-deterministic URuntimePartitionPersistent UObject name causes unstable Cooked output (RuntimePartition:DebugColor)
UE - World Creation - Worldbuilding Tools - HLOD - Jul 9, 2026During deterministic Cook / Package validation, the Cooked output of a WorldPartition map was found to vary non-deterministically between Cook runs. Diff detected in the DiffOnly Cook log:Serialize ...
Editor crashes in FAsyncLoadingThread2::ProcessLoadedPackagesFromGame when Level Blueprint references external actor
UE - World Creation - Worldbuilding Tools - Level Instances - Jun 26, 2026Adding a reference to an external actor in the level blueprint causes the package for the actor to be put in the import table of the level. In some cases, the actor package can end up calling postlo ...
Custom expression additional outputs don't work when connected to World Position Offset
UE - Rendering - Architecture - Materials - Jun 24, 2026Custom expression additional outputs are considered (0,0,0) when connected to WPO. ...
Translucent meshes randomly flicker when using VSM
UE - Rendering - Features - Jun 23, 2026Flickering can occur on translucent materials, usually in the distance when there is at least one directional light and when using VSM. Flickering seems highly dependent on framerate and timing. L ...
Apply mesh paint Blueprint instance changes and save fails
UE - Rendering - Architecture - Materials - Jun 22, 2026After mesh painting on a BP Static Mesh Actor, and "Apply instance changes to Blueprint" the added virtual texture is removed with the log:LogTexture: Display: Building texture TwoD: /Game/FirstPers ...
Rare crash in FWidgetAnimationState::OnStopped
UE - Anim - Sequencer - Jun 22, 2026The FWidgetAnimationState::OnStopped delegate is getting created when the widget anim state is being destroyed and then queued to be executed later. Something is happening between the queue and the ...
Substrate Single Layer Water material fails to compile in blendable Gbuffer mode when using the Single Layer Water BSDF node
UE - Graphics Tools - Terrain - Water - Jun 16, 2026When using Substrate in Blendable GBuffer mode, a material with the single layer water BSDF node produces a shader compiler error : MaterialEditorStats: Error: [SM6] Shader debug info dumped to: "\ ...