UUM-147355

Fixed in 6000.5.6f1

Mentioned in 2 release notes.

First fixed in 6000.5.6f1 (Jul 29, 2026).

Open on Unity Issue Tracker
VersionSectionRiskImpactNote
6000.5.6f1Fixes
Entities
FixFixed a MissingReferenceException in the Hierarchy window when a SubScene was destroyed during undo, scene unload, or domain reload.
6000.6.0b4Known IssuesCautionKnown issue6000.5.3f1: [Entities] MissingReferenceException is thrown in the Hierarchy window when entering Play mode with a scene that contains an ECS SubScene

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