UUM-153234

Fixed in 6000.7.0b7

Mentioned in 3 Unity 6 release notes.

First fixed in 6000.7.0b7 (Oct 29, 2026); relisted in 2 later releases.

All (7)Unity 7 (4)Unity 6 (3)
Open on Unity Issue Tracker
VersionSectionRiskImpactNote
6000.7.0b8Fixes
UI Toolkit
FixFixed the Editor freezing when a VisualElement was added under one of its own descendants, which now throws an ArgumentException instead.
6000.7.0b7Fixes
UI Toolkit
FixFixed the Editor freezing when a VisualElement was added under one of its own descendants, which now throws an ArgumentException instead.
6000.7.0b7Fixes
UI Toolkit
FixFixed the Editor freezing when a VisualElement was added under one of its own descendants, which now throws an ArgumentException instead.

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