Unreal Engine Issues
Unreal Engine Issues
Niagara Regression - Looping particle with Spawn Burst Instantaneous on time 0.0 flickers for a frame between loops
UE - Niagara - Jul 16, 2025Note: This worked correctly up to UE 5.4, but repros from UE 5.5 up to mainline latest. If a Niagara Emitter is set up with "Spawn Burst Instantaneous" on time 0.0, and the spawned particle(s) have ...
Bake Pose is not applied correctly when using LODSettings asset
UE - Anim - Rigging - Jul 16, 2025The Bake Pose setting does not work when using a SkeletalMesh LODSettings asset. After the change in CL22878911, the BasePose in the LODSettings asset is no longer copied to the BakePose in the skel ...
Drag-and-drop any cooked Blueprint class asset into the level viewport crashes the editor
UE - Framework - Blueprint - Jul 14, 2025Dragging any cooked Actor-based Blueprint class asset into the level editor viewport will crash the editor when it has been configured to work with cooked assets. This is a regression that started ...
Interchange framework is bypassed on the second attempt after a failed import
UE - Editor - Content Pipeline - Import and Export - Jul 14, 2025Hello! We have encountered a bug with the Interchange pipeline. When an interchange texture import is cancelled due to non-power of 2, and then the same texture is imported again without any change ...
When moving actors to the current level, their label is reset and displayed incorrectly on the Scene Outliner until the next time it is refreshed
UE - Editor - Workflow Systems - Jul 14, 2025This is a regression, it worked correctly up to UE 5.4, but repros on UE 5.5 and 5.6. Also, this seems related to [Link Removed], which was fixed by CL 40649716/40649749 and integrated into UE 5.6, ...
Channel Mask Parameter does not correctly pull through the Alpha channel from
UE - Rendering Architecture - Materials - Jul 8, 2025The ChannelMaskParameter node in the Material Graph works in most cases, but unusually does not work when extracting the value of the Alpha channel only for Vertex Color input data. ...
Assigning a static mesh to a Mutable Clip Mesh With Mesh Node can crash the editor
UE - Anim - Mutable - Jul 4, 2025Context: The Mutable plugin has a modifier node called Clip Mesh With Mesh that allows Static Mesh modifiers to be assigned as the clip mesh. Under certain circumstances, an assert can be triggered ...
Sequencer - When a subsection has negative play rate, any nested sub-subsections fail to evaluate
UE - Anim - Sequencer - Jul 3, 2025Consider a sequence hierarchy with more than two layers. If the top-level sequence uses a negative timescale on a sub-sequence, the contents inside it animate as expected, but any nested sub-sequenc ...
CPU Lightmass generates different lighting results on a landscape if executed via a commandlet vs through the editor
UE - Graphics Features - Jul 3, 2025Building lighting via commandlet and via editor are giving different results. To prevent one method from polluting the other via Swarm cache, the cache needs to be cleared in between tests. ...
In a Geometry Collection, enabling Nanite Fallback in a Nanite Enabled collection won't generate a Physics Body when Nanite is disabled
UE - Simulation - Physics - Destruction - Jun 30, 2025In a Geometry Collection, enabling Nanite Fallback in a Nanite Enabled collection won't generate a Physics Body when Nanite is disabled. To verify this, follow the steps provided in the Steps to Re ...