Unreal Engine Issues
Unreal Engine Issues
[Enhanced Input] Chord trigger fails when its referenced action lives in a lower-priority IMC
UE - Gameplay - Input - May 18, 2026Summary A UInputTriggerChordAction does not fire when the action it references (the "chording action") is mapped in a different Input Mapping Context with a lower priority than the IMC containing the ...
[CrashReport] Assertion on Mac in FCocoaRunLoopSource
UE - Platform - Apple - Jun 14, 2017This is a common crash among Mac users in 4.16. It is spread out among many separate CrashGroups, with slight variations in Callstack. Some Example CrashGroups [Link Removed] [Link Removed] [Link ...
Linux Crash Reporter can fail due to exceeding crash malloc space when generating the report
UE - Platform - Linux - Sep 16, 2026On Linux a crashing process can fail to produce a crash report at all. The crash folder is created and contains CrashContext.runtime-xml and Diagnostics.txt, but the copied log file is 0 bytes, Cras ...
[CrashReport] USpeedTreeImportFactory::FactoryCreateBinary()
UE - Editor - Content Pipeline - Import and Export - Sep 19, 2017This is a common and longstanding SpeedTree import crash that has occurred since at least 4.14 for over 100 users. This seems to be the same issue as a previous Jira from 4.10 which was closed wit ...
Ensure condition failed : SkeletalMeshLocation module on scaled SkeletalMesh
UE - Niagara - Jul 14, 2020The message in ensure is below LogOutputDevice: Error: === Handled ensure: === LogOutputDevice: Error: Ensure condition failed: (FMath::Abs(1.f - M.GetScaledAxis(EAxis::X).SizeSquared()) <= (1.e-4 ...
Crash in MaterialInstance when deleting a layer
UE - Graphics Features - May 4, 2021Repro from licensee here - [Link Removed] ...
Mover | FStanceModifier adjustment teleport on Crouch/Uncrouch can fail when child components intersect world
UE - Runtime - Character - Feb 3, 2026Context When crouching and uncrouching with Mover’s DefaultMovementSet, the pawn capsule’s half height is changed. This behavior mimics the CharacterMovementComponent. To ensure the pawn’s feet sta ...
Crash in Blueprint when clicking on Component variable name that remains after Component was deleted
UE - Gameplay - Blueprint - Jul 25, 2017This is a common crash in 4.16 and trending in the 4.17 previews. It can be reproduced by clicking on the name of a variable that remains listed in a Blueprint after the associated component has al ...
AttachRootComponentToActor being used over a network can cause an Ensure (previously an Assertion) to be triggered.
UE - Gameplay - Jan 11, 2016This is a continuation of [Link Removed]. The previous ticket changed an Assertion to an Ensure in order to stop a crash from occurring, and stated that a more complete fix would be coming in 4.10. ...
Performing a Hot Reload after changing a custom component code class can make the component unusable in Blueprints, or crash the Editor.
UE - Gameplay - Blueprint - Feb 19, 2015Performing a Hot Reload after altering a custom component code class can make the component unusable in Blueprints, and even crash the Editor. WORKAROUND: Close and re-open the Editor. ...