Building verse code with a Scene Graph prefab on the level sometimes crashes the editor

General Issues and Bug Reporting
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Summary

I couldn’t exactly catch the reason behind the crashes, but they happen once in 2-3 verse builds after I make changes to components that a prefab in the level uses. From the looks of the crash log, the issue is with layer 1 child of my prefab, the mesh component to be exact. It uses a overridden DefaultMaterial, and its collision is disabled. Here’s a screenshot of the entity.

Please select what you are reporting on:

Unreal Editor for Fortnite

What Type of Bug are you experiencing?

Verse

Steps to Reproduce

  1. Create a prefab in the content drawer
  2. Add an entity to it
  3. Add a Mesh component to the entity
  4. Set DefaultMaterial to a custom material, and set Collidable to false
  5. Add a verse component to the entity - SG_NotPlaced<public> := class<final_super>(component) {}
  6. Place the prefab onto the level
  7. Edit verse components’ code (Not SG_NotPlaced)
  8. Build verse code (Several times, until the editor crashes)

Expected Result

Successful verse build

Observed Result

Fatal error: [File:Z:\UEVFS\Root\Engine\Source\Runtime\CoreUObject\Private\UObject\UObjectGlobals.cpp] [Line: 3639]
Cannot replace existing object of a different class.
New Object: /RightBehindYou/_Verse/Assets.Objects-Transmitter-Transmitter_Body /RightBehindYou/RightBehindYou.RightBehindYou:PersistentLevel.LevelEntity.LevelEntity.EPD_Transmitter_higw4o6itmvs_1934141888.Body_Hologram_hl41hnuumyb42_1678657287.Objects-Transmitter-Transmitter_Body_0
Existing Object: /Engine/Transient.VERSE_DEAD_Objects-Transmitter-Transmitter_Body_0 /RightBehindYou/RightBehindYou.RightBehindYou:PersistentLevel.LevelEntity.LevelEntity.EPD_Transmitter_higw4o6itmvs_1934141888.Body_Hologram_hl41hnuumyb42_1678657287.Objects-Transmitter-Transmitter_Body_0 (0x00280009 0x00004000)

Platform(s)

PC