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.