Variant manager crash in UPropertyValue::HasValidResolve

UE - Editor - Content Pipeline - Variants - Nov 21, 2024

in the past we have reported a lot of VM related bugs which got fixed over time. Unfortunately, I think we have another one. Right now we're using 5.0.3 binaries from the launcher. Now the pro ...

Using the end of the curve as a weighted tangent does not yield the expected value.

UE - Anim - Runtime - Oct 16, 2023

When changing the tangent value, the last value is sometimes not 1.0 [Reproduce sample project] [Link Removed] ...

BlendListByEnum assumes that enum values are sequential

UE - Anim - Runtime - Anim Blueprints - Aug 26, 2024

FAnimNode_BlendListByEnum assumes that values within a custom enum type are sequential (ie. the index 0 = value 0, index 1 = value 1).  But this is not true of all custom enum types, for example: U ...

Optimize Data Layer runtime state replication

UE - World Creation - Worldbuilding Tools - Data Layers - Dec 7, 2023

[Link Removed]This issue occurs only when I have a lot of RDLs (I tested 2500 and 1600). I tested with 6 RDLs and had no issuesI also noticed in the server log an error when a lot of RDLs are presen ...

Oscillating Biquad Filter's Cutoff Frequency results in popping

UE - Audio - MetaSounds - Dec 8, 2022

Reproduced 7/10 times. Issue also occurs in //UE5/Release-5.0 - CL 20979098 Binary. Confirmed NOT a Regression. Additional Notes:Stacking more Biquad Filters produces a more noticeable effect, but ...

The pak file specified in PakFileRules is not created correctly

UE - CoreTech - Aug 8, 2023

The rules by which chunks are created are ambiguous and currently do not ensure that both PakFileRules and PrimaryAssetLabel settings are reflected. In this sample, depending on the PrimaryAssetLabe ...

Actors unrelated to the changelist being validated cause errors

UE - World Creation - Worldbuilding Tools - World Partition - Nov 22, 2023

When validating a changelist, unrelated errors to the changelist can appear. Here's an example of running the validation on a cl named "temp cl" which just contains a single actor "Cylinder". The A ...

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 ...

Exception on missing fiile during GC in horde storage

UE - Foundation - Horde - Storage - May 7, 2025

During GC, if a file was manually deleted (but the storage system is still track), GC can erroneously fail (and never remove the reference). This causes a backup in GC, putting the whole algorithm i ...

ChaosCacheManager is not reproducing Trailing Events

UE - Simulation - Physics - Mar 28, 2025

ChaosCacheManager (CCM) is not reproducing Trailing Events. Particles set to track Trailing Events correctly follow the position of the trailing event when the Geometry Collection (GC) is physically ...