Sequencer in 5.4.3 crashed

General Issues and Bug Reporting
1

Please select what you are reporting on:

Creative

What Type of Bug are you experiencing?

Other

Summary

I’m using 5.4.3 for virtual filmmaking and experiencing numerous crashes while animating with Sequencer. Whether it’s saving project or switching shots or just searching any asset, it can cause a crash and it’s driving me crazy.

Steps to Reproduce

  1. Create a Level Sequence.

  2. Do any operation to any obejct in Sequencer.

  3. Save the project.

Expected Result

I dont’t know, it just a saving operation?! It should be just saved.

Observed Result

Crash immediately.

Platform(s)

Windows 11

Additional Notes

The error logs are pretty much the same every time, Each of these shows up as an EntityComponentMask issue, here’s one of the error logs:

Assertion failed: !(EntityComponentMask.Contains(FBuiltInComponentTypes::Get()->Tags.NeedsLink) && EntityComponentMask.Contains(FBuiltInComponentTypes::Get()->Tags.NeedsUnlink)) [File:D:\build++UE5\Sync\Engine\Source\Runtime\MovieScene\Private\EntitySystem\MovieSceneEntityManager.cpp] [Line: 1018]

UnrealEditor_MovieScene!UE::MovieScene::FEntityManager::CreateEntityAllocation() [D:\build++UE5\Sync\Engine\Source\Runtime\MovieScene\Private\EntitySystem\MovieSceneEntityManager.cpp:1018]
UnrealEditor_MovieScene!UE::MovieScene::FEntityManager::CreateEntityAllocationEntry() [D:\build++UE5\Sync\Engine\Source\Runtime\MovieScene\Private\EntitySystem\MovieSceneEntityManager.cpp:1064]
UnrealEditor_MovieScene!UE::MovieScene::FEntityManager::GetOrCreateAllocationWithSlack() [D:\build++UE5\Sync\Engine\Source\Runtime\MovieScene\Private\EntitySystem\MovieSceneEntityManager.cpp:1094]
UnrealEditor_MovieScene!UE::MovieScene::FEntityManager::AddComponent() [D:\build++UE5\Sync\Engine\Source\Runtime\MovieScene\Private\EntitySystem\MovieSceneEntityManager.cpp:1132]
UnrealEditor_MovieScene!UObjectBaseUtility::IsA() [D:\build++UE5\Sync\Engine\Source\Runtime\MovieScene\Public\EntitySystem\MovieSceneEntityManager.h:662]
UnrealEditor_MovieScene!UMovieSceneEntityInstantiatorSystem::UnlinkStaleObjectBindings() [D:\build++UE5\Sync\Engine\Source\Runtime\MovieScene\Private\EntitySystem\MovieSceneEntityInstantiatorSystem.cpp:57]
UnrealEditor_MovieScene!UMovieSceneBoundSceneComponentInstantiator::OnRun() [D:\build++UE5\Sync\Engine\Source\Runtime\MovieScene\Private\Ent

2

I tried delete SequencerRoot, problem solved, no more crashed again.
But I need this feature, pls fix this bug.

Nope it wasn’t fix, just don’t crash as often, same error log.

3

I’m having the same issue. What do you mean by deleting SequencerRoot, The squencer file itself? That is not even a workaround.

I fiddled with it and would like to share my findings.
My case:
I have a BP actor(possessable/spawnable does not matter) in a sequencer.
This actor has a normal transfrom track with some keys.
At this point, I can move the actor around with the transformation gizmo, add keyframes and save the project with no problems.

When I add an additive transform track, not add any key frames, and the project saves again, no problems.
But, when I move the actor around, with the transformation gizmo, and add a few keyframes with the new transform, at that point, the engine crashes with the error above when I save the project.

The things directly related to the crash, I believe, are:
-BP actors
-Additive transform track
-Transformation gizmo
-And I also suspect, the level(file/actor) itself.

My workaround for now is to not to use the gizmo to move the actor, directly edit the values of the track from the sequencer.
edit_it_from_here
Or, do not use an additive transform track.

Steps to reproduce:
1-Create a level sequence.
2-And a dummy BP actor(it doesn’t happen with static meshes)
3-Add a transform track.
4-Add an additive transform tract
5-Delete the first, normal transform track(i think does not matter if it’s there or not)
6-Set a keyframe, move the actor, set a new keyframe at the new location.
7-Save all and crash.

4

I just experienced the same issue on UE 5.5.0, and can confirm this is the only workaround I’ve found yet. My animation is a subway blueprint containing child doors static meshes. I just animate the transform value of the subway and the one from the doors for the opening animation, like nothing crazy. So frustrating

5

I can confirm a similar problem also in 5.5.
It crashes when i try to modify the position keyframe of a metahuman using the gizmo. What makes it suck harder is that i haven’t found a way to modify the location parameter in sequencer using local values.

6

Can confirm. Same issue in 5.4. Geezus EPIC… Maybe fix your stuff first before releasing new versions.

7

Confirmation as well. I’m using level sequence player/play animation inside of a blueprint to trigger an animation sequence consisting of lights, material functions and keyframed movement. It plays fine until i try to exit play mode then it crashes. This is a VR project version 5.5 btw.

I have the scene set up with two grab actors, one to start sequence and one to end it/open doors. The level sequence player is at the end of grab action start. As long as I keep the Exit grab action disconnected it doesn’t crash. I can also disconnect the level sequence player and play a regular animation sequence with both strands of code connected and it works fine. Level sequence player is the common denominator, which I desperately need to make this work.

8

UPDATE: I’ve discovered that it only crashes when I have the level sequencer tab open when I hit play. So, as long as I have my code connected and do NOT have the sequencer tab opened when I hit play, it runs through and works fine, I hit exit and it comes back out as usual, no crash.

However if I have the sequencer tab opened as if I’m making edits and hit play, it will play fine until I hit exit and then will crash. I dont know if this is an error on my behalf… (Cant see how considering it’s never been an issue in the past?), or if this is a bug. I’m leaning towards a bug, because I also noticed despite my previous comment that it will still crash even when I have the level sequence player code disconnected and am using animation sequence instead so long as the level sequence tab is opened. Seems like a bug to me.

9

Hey, yeah. Same here. I’m also crashing in 5.5.1.
If your actor hierarchy allows it, you might as well keep the root at the world origin and only move the component.
In my case I’ve got some actors with skeletal meshes inside of them and they’re set to be spawnable.
Moving the actual actor around with the transform gizmo crashes UE when saving or scrubbing through the timeline.
Selecting a component and moving that around with with the transform gizmo however does not crash it.
This is still a headache and a pain to work with but it is what it is.

You’re not alone. Hope that makes everyone feel a bit better. lol