FixDeps runs on every build even without any changes

UE - Platform - Linux - Oct 21, 2016

This has been fixed for 4.15, but 4.14 was branched before the fix. Note that this issue is distinct from [Link Removed] and the fix is much simpler. Note that [Link Removed] (pull request #2839) ...

Resave commandlet broken when using BuildEnvironment = TargetBuildEnvironment.Unique;

UE - Core - Systems - May 14, 2024

The explanation from the licensee seems pretty comprehensive. Text from the UDN: We've been trying to run fixupredirects via the resavepackages commandlet, but noticed that the OFPA assets were no ...

"Invalid resource entry creating uniform buffer" when running Vulkan on Mobile

UE - Platform - Mobile - Apr 30, 2019

Android projects in 4.22.1 crash on launch with Vulkan enabled. Did NOT reproduce in 4.23 MAIN at CL 6156332 4.22.1 release CL is the same as a related fix for this ( [Link Removed] )  ...

When using OpenLevel to transition to a level with WorldPartition enabled during PIE, the log outputs "Failed to load '/Game/MapName': Can't find file."

UE - Engine Scaling - Streaming - May 31, 2022

Outputs warning logs when transitioning to the World Partition level with OpenLevel. This only occurs in PIE, not in Standalone or Package builds. In PIE, it appears that the package failed to load ...

Geometry Collection (GC) fragments are affecting the Navmesh in wrong positions

UE - Runtime - Deformable - Dec 6, 2024

Geometry Collection (GC) fragments are affecting the Navmesh in wrong positions and the identified cause is wrong indexing. Once a GC breaks, it's fragments, when big enough, are creating islands in ...

When used with First Loop Start Frame Offset and Use Animation Blueprint, the character will alternate between the specified animation and the reference pose

UE - ACT Character - Anim in Engine - Jan 30, 2023

If you use StartFrameOffset set to 1 or higher in conjunction with the Use Animation Blueprint, the character's animation will be rough towards the end of the section. Specifically, it seems that th ...

Mobile Map loading times have increased from 4.12 to 4.13

UE - Platform - Mobile - Oct 4, 2016

The loading time from 4.12 to 4.13 on mobile devices seems to have increased quite a bit. My results: 4.12.5 Windows 7 - Launch On: Loading Level 2 - .51 Loading Level 3 - .74 Loading Level 1 - .73 ...

Paper2D performance regression due to TArray resizing

UE - Graphics Features - Aug 16, 2019

We've noticed after upgrading our heavy Paper2D project to 4.22 that tilemap performance has been massively degraded compared to previous versions. After some digging we found out that it's due to a ...

Sequencer causes 3DWidget on BP vectors to snap to Actor when active

zComponent - Archive - Nov 15, 2025

When we have Vectors in BP with Show 3D Widget enabled, the Transform Widget would always snap back to the Actor after we move the 3D Widget in-world. [Link Removed] Removing the _DaySequenceActor ...

Open Formats: Interchange Import Runtime - Interchange ImportAssetAsync runtime GLB import — materials, textures, tangents, and shaders non-functional in packaged builds (6 issues, UE 5.7.4)

UE - VEI - Open File Formats - Apr 30, 2026

Description* We are using Interchange's `UInterchangeManager::ImportAssetAsync()` to import GLB files at runtime in a packaged (Shipping) application. The orchestration layer (`ImportInternal` in `In ...