FKeyHandle internal static atomic counter can overflow on long running games depending on usage pattern

UE - Anim - Sep 24, 2025

Structure FKeyHandle stores an internal index, which is initialized from a static atomic counter in the default constructor: +----- FKeyHandle::FKeyHandle() { | static std::atomic<uint32> LastKey ...

Chaos Fields: LS_MasterField continuously creates components every frame and never cleans them up

UE - Runtime - Deformable - Mar 25, 2026

While active and ticking, the built-in FS_MasterField actor instance continuously creates several new components every frame, which are never cleaned up until the actor is destroyed. This can happen ...

UPlacementSubsystem does not respect AssetFactories priorities, which is inconsistent with UEditorEngine::ActorFactories and makes it impossible to override placed actor type when dragging asset from Content Browser to Level Editor Viewport.

UE - Editor - Workflow Systems - Mar 30, 2026

Note: This issue was reproduced in UE 5.7, and it works correctly in UE 4.27. Prior to CL 24938100 (between UE 5.1 and 5.2), all existing factories were discovered and registered during engine init ...

Editor will crash when Blueprint Details Panel is dragged across the Event Graph

Tools - May 6, 2015

When dragging the Details Panel in a Blueprint across the event graph the editor will crash. [Link Removed] ...

Crash when setting console command for shadow max resolution to 1

UE - Graphics Features - May 29, 2015

When setting the console command r.shadow.MaxResolution to a value of 1 will cause a crash. CrashReporter: [Link Removed] ...

Visible dithered quantization to remove banding in New Temporal AA Quality

UE - Graphics Features - Oct 6, 2015

Since changing the temporal history buffer to 11:11:10 from FP16, it looks as there is visible dithered quantization to remove banding when rendering. (Taken from conversation on Forum Post linked f ...

VC Runtime not in UnrealLightmass temp directory; causing lightmass build errors

UE - Foundation - Cpp Tools - UnrealBuildTool - Oct 14, 2015

A Redistribute file for VS 2015 is needed to build lightmass, but this is not currently included with the engine. If a user does not have VS 2015 installed, lightmass will fail with this error: Un ...

Split-screen players not rendering

UE - Graphics Features - Feb 11, 2015

When using the Create Player node to setup split-screen multiplayer, only the last player created will show properly. All other players experience render issues for their character and environment. ...

Creating 3 player splitscreen causes viewport to go black on PIE

UE - Graphics Features - Feb 13, 2015

If a game is set to play with 3 player splitscreen, starting the came will cause the viewport to go completely black. Does not occur with 2/4 players. Does not occur in standalone ...

External Reference Spam when converting projects to 4.9

UE - Foundation - Core - Cooker - Sep 1, 2015

Map Check message log gets spammed with External Reference warnings when a project is converted to 4.9 from a previous engine version. These warnings don't seem to actually do anything to projects o ...