Drop a GridPane.
Drop a Button in cell 1,1.
Delete the row 1 (i.e. the one with the Button), then undo.
The following exception raised.
Although we get the message "Failed to undo", the tool seems to behave correctly.

Failed to undo. 2
java.lang.ArrayIndexOutOfBoundsException: 2
at javafx.scene.layout.GridPaneDesignInfo.getCellBounds(GridPaneDesignInfo.java:93)
at com.oracle.javafx.authoring.stage.v2.handles.gridpane.GridPaneMosaic.computeCellOrGapQuad(GridPaneMosaic.java:1041)
at com.oracle.javafx.authoring.stage.v2.handles.gridpane.GridPaneMosaic.addCellAndGaps(GridPaneMosaic.java:828)
at com.oracle.javafx.authoring.stage.v2.handles.gridpane.GridPaneMosaic.<init>(GridPaneMosaic.java:196)
at com.oracle.javafx.authoring.stage.v2.handles.gridpane.GridPaneSelectionHandles.createGridDividerChildren(GridPaneSelectionHandles.java:200)
at com.oracle.javafx.authoring.stage.v2.handles.gridpane.GridPaneSelectionHandles.createChildren(GridPaneSelectionHandles.java:179)
at com.oracle.javafx.authoring.stage.v2.handles.GenericSelectionHandles.update(GenericSelectionHandles.java:39)
at com.oracle.javafx.authoring.stage.v2.handles.TrackerV4.attachToTarget(TrackerV4.java:332)
at com.oracle.javafx.authoring.stage.v2.handles.TrackerV4.trackerSceneDidChange(TrackerV4.java:282)
at com.oracle.javafx.authoring.stage.v2.handles.TrackerV4.access$200(TrackerV4.java:28)
at com.oracle.javafx.authoring.stage.v2.handles.TrackerV4$4.changed(TrackerV4.java:70)
at com.oracle.javafx.authoring.stage.v2.handles.TrackerV4$4.changed(TrackerV4.java:67)
at com.sun.javafx.binding.ExpressionHelper$SingleChange.fireValueChangedEvent(ExpressionHelper.java:196)
at com.sun.javafx.binding.ExpressionHelper.fireValueChangedEvent(ExpressionHelper.java:100)
at javafx.beans.property.ReadOnlyObjectWrapper$ReadOnlyPropertyImpl.fireValueChangedEvent(ReadOnlyObjectWrapper.java:195)
at javafx.beans.property.ReadOnlyObjectWrapper.fireValueChangedEvent(ReadOnlyObjectWrapper.java:161)
at javafx.beans.property.ObjectPropertyBase.markInvalid(ObjectPropertyBase.java:130)
at javafx.beans.property.ObjectPropertyBase.set(ObjectPropertyBase.java:163)
at javafx.scene.Node.setScene(Node.java:661)
at javafx.scene.Parent$1.onChanged(Parent.java:425)
at com.sun.javafx.collections.VetoableObservableList.callObservers(VetoableObservableList.java:83)
at com.sun.javafx.collections.ObservableListWrapper.add(ObservableListWrapper.java:154)
at com.sun.javafx.collections.VetoableObservableList.add(VetoableObservableList.java:167)
at com.sun.javafx.collections.ObservableListWrapper.add(ObservableListWrapper.java:144)
at com.oracle.javafx.authoring.StageView.projectSelectionRevisionDidChange(StageView.java:928)
at com.oracle.javafx.authoring.StageView.access$700(StageView.java:70)
at com.oracle.javafx.authoring.StageView$9.changed(StageView.java:183)
at com.oracle.javafx.authoring.StageView$9.changed(StageView.java:180)
at com.sun.javafx.binding.ExpressionHelper$SingleChange.fireValueChangedEvent(ExpressionHelper.java:196)
at com.sun.javafx.binding.ExpressionHelper.fireValueChangedEvent(ExpressionHelper.java:100)
at javafx.beans.property.IntegerPropertyBase.fireValueChangedEvent(IntegerPropertyBase.java:123)
at javafx.beans.property.IntegerPropertyBase.markInvalid(IntegerPropertyBase.java:130)
at javafx.beans.property.IntegerPropertyBase.access$100(IntegerPropertyBase.java:69)
at javafx.beans.property.IntegerPropertyBase$Listener.invalidated(IntegerPropertyBase.java:251)
at com.sun.javafx.binding.ExpressionHelper$Generic.fireValueChangedEvent(ExpressionHelper.java:359)
at com.sun.javafx.binding.ExpressionHelper.fireValueChangedEvent(ExpressionHelper.java:100)