USD Export - crashes when sub level holds level instance

UE - Editor - Content Pipeline - USD - Mar 27, 2026

The engine is crashing when the user tries to export from a persistent level with a sub level that contains a level instance. ...

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

UE - Simulation - Visual - 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 ...

Renamed controls creating duplicate curves in sequencer that once fixed up cause selection issues.

UE - Anim - Rigging - Control Rig - Mar 25, 2026

When a control is renamed after it has already been animated in a sequence, the control curve name map needs to be fixed up. Once it is fixed, selecting the control in the world will not map the sel ...

UMG Viewmodel Plugin -- When setting up View Bindings, several arithmetic and comparison functions are missing from the "Conversion Functions" list

UE - Editor - UI Systems - UMG - Mar 20, 2026

When setting up View Bindings from the "UMG Viewmodel Plugin" on a Widget Blueprint, it is possible to select a compatible "Conversion Function" from the list of available bindings. By default, the ...

Chooser with Gameplay tag as output causes Evaluate Choose to not compile.

UE - Anim - Gameplay - Mar 20, 2026

When using a No Primary Result Chooser that contains an FGameplayTag parameter, an Evaluate Chooser node using that chooser will cause a compilation error: LogBlueprint: Error: [AssetLog][PathToPro ...

Nanite Displacement Bounds Mismatch Causes Floating Terrain Artifacts on Landscape

UE - Rendering - Graphics Features - Nanite - Mar 19, 2026

Summary When Nanite Tessellation (Nanite Displacement) is enabled on a Landscape in UE 5.7.3, scaling the Displacement value via Multiply nodes in the material graph causes floating terrain ghost a ...

When CommonTabListWidgetBase and ScrollBox are arranged vertically, tabs within CommonTabListWidgetBase momentarily become selected when scrolling the ScrollBox upward

UE - Editor - UI Systems - UMG - Mar 19, 2026

When attempting to scroll the ScrollBox upward, the cursor briefly shifts focus to another widget (CommonTabListWidgetBase). When logging this behavior using LogSlate VeryVerbose, it can be observed ...

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 ...

Modular rig - Hindleg thigh bug when switching from IK to FK

UE - Anim - Rigging - Control Rig - Mar 16, 2026

The thigh FK controller of the hingleg in modular rig doesn't move the thigh bone, causing bad deformation on the mesh around character's thigh area. ...

Cursor radius set via FSlateApplication::SetCursorRadius is ignored during FHittestGrid hit testing

UE - Editor - UI Systems - Slate - Mar 16, 2026

The cursor radius configured through FSlateApplication::SetCursorRadius() is not respected during Slate hit testing. The radius value is correctly stored in FSlateApplication and passed into FHittes ...