Unreal Engine Issues
Unreal Engine Issues
Crash occurs in the Editor when multiple instances of the same Blueprint are selected in the level and the Reset to Default button next to a component of the Blueprint is clicked in the Details panel
UE - Gameplay - Blueprint - May 4, 2017When multiple instances of a Blueprint in a level are selected, any component added to that Blueprint's parent class in code will appear in the Details panel with the words "Multiple Values" and a R ...
Alt tabbing into the Blueprint Editor while a Microsoft IME keyboard is active causes the editor to freeze
Tools - May 15, 2017If you change focus to the Blueprint Editor (Alt+tab) while a Microsoft IME keyboard is active, the editor will freeze for a short time. The duration of the freeze is dependent on the number of blue ...
Is Valid is true in PIE but prints false in package build
UE - Editor - UI Systems - May 18, 2017When using the IsValid node inside of a Widget blueprint with the Widget as the selected asset, the string will print as true in the Editor, but prints as false in the packaged build of the game. ...
AssetManager can load blueprints of the wrong type when redirectors exist
UE - Gameplay - Sep 29, 2017The logic in the AssetManager to determine if a scanned Blueprint should be added to the primary asset directory is wrong if that blueprint has an active redirect targeting it. The simplest way to r ...
[CrashReport] Mac crash - UE4Editor-SlateCore.dylib!SWindow::IsVisible()
UE - Platform - Apple - Oct 12, 2017This is a trending Mac crash coming out of the 4.18 previews. Most of the project titles experiencing this crash mention "AR" It is the exact same callstack and crashgroup as [Link Removed], but th ...
fbx attribute curve import do not support correctly tangent at the start end end of the curve
UE - Editor - Content Pipeline - Import and Export - Sep 2, 2020We are not reading all the key flags and we do not import correctly start key and end key tangent. I create a shelve but this is not the complete fix, we must do this only if we do not have fbx ket ...
Copying collapsed graph with a node with a custom Exec pin results in duplicate pin name
UE - Framework - Blueprint Editor - Aug 17, 2022When duplicating a collapsed blueprint graph which has a node with a custom Exec pin, this results in blueprint compilation error that a duplicate named pin is found. Duplicated exec pins aren't ass ...
FAnimUpdateRateParameters::GetInterpolationAlpha appears to be returning an invalid value for TrailMode
UE - Runtime - Animation - Aug 5, 2023It appears that FAnimUpdateRateParameters::GetInterpolationAlpha is not returning a sensible value when running in TrailMode. Currently the only variable in the calculation is EvaluationRate which ...
FInstancedStruct member uproperties are not cached when "Generate Optimized Blueprint Component Data" is enabled
UE - Framework - Blueprint - Nov 18, 2025A licensee has encountered an issue where their FInstancedStruct isn't being gathered into CachedPropertyData when "Generate Optimized Blueprint Component Data" is enabled. The changes in [Link Remo ...
Instanced Actors: Moving element in editor is not undoable
UE - Engine Scaling - Mass - May 30, 2026Context Instanced Actors can be moved by unchecking Lock Instance Locations on an IAM, and double-clicking into the actor → comp → instance to select an instance. Problem Moving an IA via the giz ...