UUM-140859

Fixed in 6000.4.9f1

Mentioned in 5 release notes.

First fixed in 6000.4.9f1 (May 27, 2026); relisted in 4 later releases.

Open on Unity Issue Tracker
VersionSectionRiskImpactNote
6000.5.0f1Fixes
Editor
FixFixed "ArgumentNullException" is thrown when dragging a selector between greyed-out built-in child elements in UI Builder.
6000.5.0b11Fixes
Editor
FixFixed "ArgumentNullException" is thrown when dragging a selector between greyed-out built-in child elements in UI Builder.
6000.5.0b10Fixes
Editor
FixFixed "ArgumentNullException" is thrown when dragging a selector between greyed-out built-in child elements in UI Builder.
6000.5.0b10Fixes
Editor
FixFixed "ArgumentNullException" is thrown when dragging a selector between greyed-out built-in child elements in UI Builder.
6000.4.9f1Fixes
Editor
FixFixed "ArgumentNullException" is thrown when dragging a selector between greyed-out built-in child elements in UI Builder

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