RectControl.AllowAutoDeactivate

From Xojo Documentation

Property (As Boolean )
aRectControl.AllowAutoDeactivate = newBooleanValue
or
BooleanValue = aRectControl.AllowAutoDeactivate

New in 2019r2

Supported for all project types and targets.

Determines whether the control should be deactivated (on macOS) when the parent window is deactivated. The default is True.