FViewElementPDI::DrawLine calls for SDPG_World are not rendered in PIE or in Game

UE - Rendering Architecture - RHI - Jan 7, 2026

When View.Family->EngineShowFlags.CompositeEditorPrimitives is false in the function RenderEditorPrimitivesForDPG. This code picks which version of the batched lines to renderconst FBatchedElements ...

CommonUI: FUITag, FUIActionTag variables can't connect with blueprint wildcard Equals node

UE - Editor - UI Systems - Jan 5, 2026

Context UITag and UIActionTag are blueprint-exposed struct classes that derive from GameplayTag. GameplayTag variables can be compared in blueprint with ==. Under the hood, the node maps to  UBlue ...

MultiProcessCook Shader Symbols fail to write when two workers race and try to write them at the same time

UE - Foundation - Data Pipeline - Cooker - Jan 4, 2026

When shadersymbols are requested, cooking shaders writes the symbol files into {Project} /Saved/ShaderSymbols/<PlatformName>. These symbols are written by the function FShaderSymbolExport::Write ...

Buildgraph: "After" paramter on nodes doesnt add a dependancy

UE - Foundation - Horde - BuildGraph - Dec 22, 2025

Adding the after parameter to a node, does not add a dependency like requires does. The documentation indicates that it would be triggered after another node. This was interpretated by the licensee ...

Virtual Memory leak when using specific rendering settings in the template project

UE - Rendering Architecture - Dec 20, 2025

When a project is run with these settings in a template project, untracked virtual memory increases. Cvars r.GBufferFormat 3 r.Lumen.TraceMeshSDFs 1 r.Lumen.TranslucencyReflections.FrontLayer.Enab ...

Skeletal Mesh BLAS updates when not animating

UE - Rendering Architecture - RHI - Dec 19, 2025

The BLAS for Skeletal Meshes that don't move, or tick get updated every frame even if the animation and skin cache aren't updated. This adds over 1ms to update time. The only exception is if the sk ...

When r.SSR.Stencil is enabled, there is wrong logic observed.

UE - Graphics Features - Dec 19, 2025

When r.SSR.Stencil is enabled, the areas with high roughnesss are not discarded and Unlit materials are incorrectly handled. See the linked EPS case (Additional Info URL) for a full explanation of ...

Crash during .zfprj import when Feature detection quality is set to High and Use mosaic images as feature source is set to Yes

RS - Alignment - Dec 19, 2025

Found in 2.0.0.118621 (R200). It appears that the combination of Feature detection - High and Use mosaic images as feature source during .zfprj LiDAR import - Yes. causes a crash. Outcome: RS ...

Subobject ComponentClass overrides cause failing assertions due to UObject reconstruction on AsyncLoadingThread

UE - Framework - Blueprint - Dec 19, 2025

Context The blueprint editor allows you to override an actor component's class in derived blueprints (component details panel -> Component Class). [Image Removed] Problem When a blueprint and it ...

Call In Editor functions not working in blueprints

UE - Editor - Developer Usability - Dec 19, 2025

Context When selecting a component on an actor, any CallInEditor functions on the component's class appear as buttons in the details panel. Problem The CallInEditor functions don't execute in Blu ...