Volumetric Translucent Shadows will only work if you select the mesh, doesn't show up in game

UE - Graphics Features - Aug 18, 2015

When using Volumetric Translucent Shadows for static meshes the shadows will only work if the mesh is selected. When the mesh is deselected it will not render. This worked in 4.8.3, but is broken ...

Unexpected behavior from moving multiple widget components with render transform

UE - Editor - UI Systems - May 10, 2017

Unexpected behavior occurs from moving multiple widget components with render transform applied to them. The individual components seem to change relative position or rotation when being clicked and ...

Does FSlateElementBatcher::AddCachedElements need to check if r.HDR.UI.CompositeMode is enabled?

UE - Editor - UI Systems - Aug 28, 2024

When a specific configuration of HDR cvars are set, PIE in a New Editor Window will not render the game world. Settings (For DefaultEngine.ini): ```[SystemSettings] r.AllowHDR=1 r.HDR.Display.Color ...

Config entries to re-open asset windows are deleted if the Editor is shut down while a debugger is attached

Tools - Apr 17, 2019

When the "Restore Open Asset Tabs on Restart" option is turned on in the Editor Preferences window, closing the Editor while a debugger is attached appears to remove any saved asset tabs from the Ed ...

JsonObjectToUStruct removes _ClassName from input FJsonObject, breaking repeated deserialization

UE - Foundation - Mar 18, 2026

FJsonObjectConverter::JsonObjectToUStruct removes _ClassName from nested JSON objects during deserialization. Removing Obj->RemoveField(ObjectClassNameKey) from ConvertScalarJsonValueToFPropertyWit ...

Cannot change the Strength value on a Physics Constraint in the Viewport Details panel

UE - Simulation - Physics - Jan 5, 2017

Cannot change the Strength value on a Physics Constraint to anything other than the default value in the Viewport Details panel. When changed the editor will pause and replace the value with — This ...

Pre-UE5 serialized FVariant FVector data corruption when deserialized in UE5

UE - Framework - LWC - Jan 15, 2024

FVariant is a struct that implements a union of data types, including FVector. When assigning an FVariant an FVector value in engine versions UE 4.27 or earlier, the FVariant will deserialize incorr ...

Calling UBlueprintMapLibrary::GenericMap_Find with a non-existent key causes a memory leak

UE - Framework - Blueprint - Apr 15, 2025

When Calling UBlueprintMapLibrary::GenericMap_Find with a non-existent key, the function construct the default structure in-place on the given pointer without destroying the object. This behavior ca ...

Child Actor Component Actor Duplicates and Persists After Play

UE - Gameplay - Sep 26, 2019

When an actor spawns another actor using AddChildActorComponent that comes alphabetically before it based on blueprint name it will spawn an extra actor that will persist when the scene is stopped d ...

Using a FormatText node with Specifier in the same graph as an empty Macro will freeze the editor

UE - Gameplay - Blueprint - Jun 17, 2016

Using a FormatText node with Specifier in the same graph as an empty Macro will freeze the editor. Not using the Specifier or deleting the unused Marco will allow the BP to compile fine. **Only rep ...