Unreal Engine Issues
Unreal Engine Issues
Crash When Loading Cooked Material Assets in Editor Due to Shader Serialization
UE - Rendering - Architecture - Shaders - Aug 27, 2025In Unreal Engine 5.6+, the new shader serialization logic in FShaderMapResourceCode::Serialize does not correctly handle cooked assets that are loaded back into the editor (e.g., from a mounted .pak ...
Cooker is asserting in Class.h on UE 5.7.1
UE - CoreTech - Dec 18, 2025From the linked EPS case: ---------------------------- In UE 5.7 there were some changes to how Enum member names are stored. This change introduces an assert when cooking using the Editor Debug e ...
UMG Widgets using User Interface Material Domain do not render on Android Devices
UE - Platform - Mobile - Jan 19, 2016When using a Blueprint Widget that has an image using a material in the User Interface Material Domain will not render when it's a newly created project in 4.11. However, if you were to copy a proje ...
Packaging Error When Setting Recast Nav Mesh Runtime Generation
UE - AI - Jan 25, 2016Setting the Runtime Generation on the Recast Nav Mesh to a different preset than what is set in the Project Settings causes an error to appear upon trying to package the project, and causes the pack ...
FOnlineSessionLive leaves inconsistent state when FindSessions or CreateSession fail.
UE - Networking - Nov 28, 2016FOnlineSessionLive::CreateSession creates the session early into the method. Later, the method can fail but the session and is never cleared up (see the various catch statements in the tasks which o ...
Ambiguous Search Warning After Recompiling Blueprint of an Object Involved in a Level Sequence
UE - Anim - Sequencer - Apr 18, 2017The licensee is receiving an ambiguous search warning after recompiling the blueprint of an object involved in a level sequence that is contained in a hidden sublevel (which is then loaded and made ...
Enum with "MAX" element at other than the last element removes user defined last element
UE - Foundation - Core - Oct 18, 2019FNativeClassHeaderGenerator::ExportEnum produces this behavior. If an enum has “MAX” somewhere in the array, it removes last element. I tested my code to fix the issue.// code placeholder bool UE ...
Regression - Nav mesh is not generated on BSP brushes after loading a map
UE - AI - Navigation - Dec 18, 2024In UE 5.5, when loading a map and selecting "Build – Build Paths", the nav mesh is not generated on any BSP brushes (although it is correctly generated in static meshes). This did not happen in earl ...
Regression - Nav mesh is not generated on BSP brushes after loading a map
UE - AI - Navigation - Jan 14, 2025In UE 5.5, when loading a map and selecting "Build – Build Paths", the nav mesh is not generated on any BSP brushes (although it is correctly generated in static meshes). This did not happen in earl ...
JsonObjectToUStruct removes _ClassName from input FJsonObject, breaking repeated deserialization
UE - Foundation - Mar 18, 2026FJsonObjectConverter::JsonObjectToUStruct removes _ClassName from nested JSON objects during deserialization. Removing Obj->RemoveField(ObjectClassNameKey) from ConvertScalarJsonValueToFPropertyWit ...