UUM-146454

Fixed in 6000.6.0b6

Mentioned in 5 release notes.

First fixed in 6000.6.0b6 (Aug 4, 2026); relisted in 2 later releases.

Open on Unity Issue Tracker
VersionSectionRiskImpactNote
6000.7.0a4Fixes
UI Toolkit
FixFixed an Editor crash that would occur when trying to undo a VisualTreeAsset or StyleSheet change past the last import.
6000.7.0a4Fixes
UI Toolkit
FixFixed an Editor crash that would occur when trying to undo a VisualTreeAsset or StyleSheet change past the last import.
6000.6.0b6Fixes
UI Toolkit
FixFixed editor crashing when trying to undo a VisualTreeAsset or StyleSheet change past the last import. (UUM-146454) First seen in 6000.6.0b3.
6000.7.0a3Known Issues
UI Toolkit
BlockerKnown issueFixed an Editor crash that would occur when trying to undo a VisualTreeAsset or StyleSheet change past the last import. (UUM-146454) Fixed in 6000.7.0a4.
6000.6.0b5Known Issues
UI Toolkit
CautionKnown issueFixed editor crashing when trying to undo a VisualTreeAsset or StyleSheet change past the last import. (UUM-146454) First seen in 6000.6.0b3. Fixed in 6000.6.0b6.

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