With Use Fixed Frame Rate turned on, time-based elements of the Editor appear to operate at incorrect rates.

Tools - Oct 29, 2015

Turning on the Use Fixed Frame Rate option for a project causes time-based elements of the Editor to operate at incorrect rates. ...

BP timelines: when converting internal curve to external, the external curve isn't used until BP is recompiled

UE - Gameplay - Blueprint Editor - Aug 28, 2023

Blueprint timelines: when converting an internal curve to an external curve asset, the curve asset's data isn't used until the blueprint is recompiled. This is confusing as there is no indication th ...

Using Tortoise SVN causes the engine's source control to be inconsistent

Tools - Jun 16, 2015

If a user decides to use Tortoise SVN, the error messages given for needing to have things checked out is inconsistent. If there is a blueprint which references another blueprint, and the reference ...

Reset to default behavior for arrays is inconsistent about updating customized struct headers

UE - Editor - Workflow Systems - Jun 22, 2023

The behavior for resetting the default for customized struct properties is inconsistent and needs to be reviewed and fixed. Currently we see this behavior:In non-array properties, the header will be ...

ARKit portrait image aspect ratio incorrect on iPhone 6s,7, probably all phones.

UE - Platform - XR - Nov 29, 2017

As described in this UDN thread, the iPhone 7 manifests incorrect image aspect ratiohttps://udn.unrealengine.com/questions/403841/ios-arkit-portrait-mode-stretching-on-iphone-7.html [Link Removed] ...

Importing static mesh while a PIE session is running permanently breaks nanite on the asset

UE - Editor - Content Pipeline - Import and Export - Mar 12, 2025

Importing a Static Mesh during PIE can cause it to never enable Nanite, even if it reports that Nanite is enabled. To re-enable Nanite on the mesh, the asset needs to be deleted and imported again ...

NPC - Instances does not get updates from changes to the parent Niagara Parameter Collection in the editor

UE - Niagara - Oct 4, 2024

When 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 ...

Always Relevant actor may replicate incorrect movement mode when the walkable floor becomes irrelevant

UE - Gameplay - Player Movement - Feb 26, 2024

When the character class is set to always relevant, if a client travels very far away from another character, such that the character is relevant but the component they're standing on is not (but al ...

Inaccurate motion vectors when using different position binding in renderer

UE - Niagara - Rendering - Jul 27, 2023

Even though the particles are not moving, and the velocity is zero, the output motion vectors are non-zero. This seems to only happen if using two sources of particle positions.  ...

Packaged iOS project incorrectly includes level not selected to be cooked

UE - Foundation - Core - Cooker - Oct 11, 2017

When packaging for iOS on a Mac, the default level for a project will always be included in the packaged project even if it was not selected to be cooked and packaged. The expected behavior is that ...