Unreal Engine Issues
Unreal Engine Issues
Children of editor-only actors do not maintain correct transforms when placed inside level instances for PIE and cooked builds
UE - World Creation - Worldbuilding Tools - Level Instances - Oct 20, 2025We have found an issue where children of editor-only actors get wrong transforms in PIE and cooked builds when placed inside level instances. This affects both engine version 5.5 and 5.6. The issue ...
FileSystemDerivedDataBackend may output a corrupted access log
UE - Foundation - Core - Derived Data - May 20, 2021This problem is caused by the AccessLogWriter has not been flushed at the termination. The following workaround flushes the Writer.class FFileSystemDerivedDataBackend : public FDerivedDataBackendInt ...
Crash when trimming animation and then undoing action
UE - Runtime - Animation - May 30, 2023Repro rate: 3/3 times This is a regression as the issue does not occur in 5.1.1 ...
Machine ID is not being shown on the crashreporter website
UE - Foundation - Core - CrashReportClient - Jan 13, 2017This is a regression from 4.14.3 ...
Nanite Displacement Bounds Mismatch Causes Floating Terrain Artifacts on Landscape
UE - Rendering - Graphics Features - Nanite - Mar 19, 2026Summary 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 ...
FGameplayTagCountContainer::Reset() leaves explicit tag state and causes counts to accumulate
UE - Gameplay - Gameplay Tags - Aug 4, 2026[Summary] In UE 5.7 and later, if a tag is added once to an FGameplayTagCountContainer, the container is reset, and the same tag is added once more, GetExplicitTagCount() returns 2 instead of the e ...
FBX: Camera imports to Matinee with skewed position and rotation
UE - Editor - Content Pipeline - Import and Export - Aug 27, 2013Branch Build Label Changelist UE4-Main UE4_[2013-08-27_14.24] 1799942 DESCRIPTION: When importing an animated camera from Maya into Matinee, the placement of the camera is changed (shifted 90 ...
Walking into some destructibles crashes the editor
UE - Simulation - Physics - Destruction - Aug 20, 2015Submitted by a licensee on UDN. I verified it and have attached the test level that he provided. In the test map. some boxes fall and break. Walking straight into the boxes causes the editor to cra ...
NPC - Instances does not get updates from changes to the parent Niagara Parameter Collection in the editor
UE - Niagara - Oct 4, 2024When an Niagara Parameter Collection (NPC) is selected as the parent Collection for an NPC Instance (NPCI), all of its current parameters are carried over to the NPCI with their current values as th ...
Niagara - When Interpolated Spawning is disabled, the first frame of each particle unexpectedly does not take into account the Particle Update stage
UE - Niagara - Feb 28, 2025Foreword: Even if the behavior described here is by design, it is rarely (if ever) expected or desired. This was discussed and agreed to be treated as a bug. Explanation below. When interpolated sp ...