Unreal Engine Issues

Screen Aligned(Velocity) particles deform at low velocity

Screen aligned particles with very low velocity will squash in 4.23+ (No squashing in 4.22) Confirmed in 4.25 MAIN at CL 10333042 ...

Copying an InstancedStaticMeshComponent does not render correctly

Material cannot be set in MaterialInterface of NiagaraParameterCollection

When MaterialInterface is added to UserParameter of NiagaraSystem, Material can be set in Properties. Also, in UE4main CL15988344, there is no MaterialInterface item in the NiagaraParameterCollecti ...

'recompileshaders changed' doesn't work

The issue is already fixed in UE5 by CL 14368553. This Jira is created for cherrypick into UE4 ...

Crash in FMacApplication::FindScreenByCocoaPosition when using the mouse in the ILIAD plugin.

I think this could occur anytime but is probably very rare. However using this plugin from the reported UDN makes it much easier to repro as they are calling FMacApplication::ConvertCocoaPositionTo ...

[CrashReport] UE4Editor-MovieSceneTracks!UMovieSceneComponentMobilitySystem::RestorePreAnimatedState

[CrashReport] UE4Editor-MovieSceneTracks!UMovieSceneComponentMobilitySystem::RestorePreAnimatedState(IMovieScenePreAnimatedStateSystemInterface::FPreAnimationParameters const &) [MovieSceneComponent ...

When rendering a reflection capture, the lightmap may be rendered without finishing streaming.

This problem occurs when you do a lighting build. It does not occur when the reflection capture is done by itself. ...

Timelines do not parse "," in numeric fields the same as the rest of the editor

GPU Crash may occur when using Nanite Tesselation on landscape with several shadow casting local lights

The GPU may time out in NaniteSplit when drawing VSM shadows for Nanite Tessellated landscape with in a scene with several local shadowed point lights. The issue doesn't reproduce in 5.6, likely to ...

Specular Scale 0 on Light still affects Groom asset

When a light's Specular Scale is set to 0, the specular still affects hair / groom assets. The specular of other assets (like a shiny static mesh in the scene) is properly affected by the change.  ...