Unconnected link end snapping

GoJS
3

I also have the tool:

function SnappingRelinkingTool() {
	go.RelinkingTool.call(this);
}

go.Diagram.inherit(SnappingRelinkingTool, go.RelinkingTool);

SnappingRelinkingTool.prototype.doMouseMove = function () {

	var diagram = this.diagram;
	if (diagram.toolManager.draggingTool.isGridSnapEnabled === true) {
		var e = this.diagram.lastInput;
		var grid = this.diagram.grid;
		e.documentPoint = e.documentPoint.copy().snapToGridPoint(grid.gridOrigin, grid.gridCellSize);
		e.viewPoint = e.diagram.transformDocToView(e.documentPoint);
	}
	go.RelinkingTool.prototype.doMouseMove.call(this);
}

and my diagram:

var diagram = $$( go.Diagram, canvasId, {

   
    commandHandler: $$( DrawCommandHandler ),
    //"ChangedSelection" : updateMultiSelectionPart,
    "grid.gridCellSize": new go.Size( 30, 20 ),
    "undoManager.isEnabled": true,
    "undoManager.maxHistoryLength": -1,
    "panningTool.isEnabled": true,
    "dragSelectingTool.isEnabled": false,
    "draggingTool.dragsLink": true,
    "draggingTool.isGridSnapEnabled": true,
    linkReshapingTool: $$(SnapLinkReshapingTool),
    relinkingTool: new SnappingRelinkingTool(),
    "relinkingTool.isUnconnectedLinkValid": true,
    "animationManager.isEnabled": false,
} );

I apologize that I don’t know exactly what is different between ours. I am just coming back into this project. I will look again tomorrow to see what else differs. Thanks for your help