fix an error with a previous fix for handling stacking, see #425 and #…

…424
phetsims · Oct 26, 2023 · 522d1f0 · 522d1f0
1 parent 95e21a8
commit 522d1f0
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/js/common/model/UserMovableModelElement.js b/js/common/model/UserMovableModelElement.js
@@ -104,7 +104,7 @@ class UserMovableModelElement extends ModelElement {
     );
 
     // TODO: likely this check should not be graceful and should actually be right, https://github.com/phetsims/energy-forms-and-changes/issues/424
-    if ( supportingSurface.positionProperty.hasListener( this.surfaceMotionObserver ) ) {
+    if ( !supportingSurface.positionProperty.hasListener( this.surfaceMotionObserver ) ) {
       supportingSurface.positionProperty.link( this.surfaceMotionObserver );
     }
     this.supportingSurface = supportingSurface;