SelectionHelper: ensure DOM cleanup (#30473)

* SelectionHelper: ensure DOM cleanup

* SelectionHelper use el.remove() pattern

examples/jsm/interactive/SelectionHelper.js

@@ -59,6 +59,8 @@ class SelectionHelper {
 		this.renderer.domElement.removeEventListener( 'pointermove', this.onPointerMove );
 		this.renderer.domElement.removeEventListener( 'pointerup', this.onPointerUp );
 
+		this.element.remove(); // in case disposal happens while dragging
+
 	}
 
 	onSelectStart( event ) {
@@ -95,7 +97,7 @@ class SelectionHelper {
 
 	onSelectOver() {
 
-		this.element.parentElement.removeChild( this.element );
+		this.element.remove();
 
 	}