diff --git a/frontend/src/services/util-registry/util-registry.js b/frontend/src/services/util-registry/util-registry.js
index dd4a38af6..b342d812a 100644
--- a/frontend/src/services/util-registry/util-registry.js
+++ b/frontend/src/services/util-registry/util-registry.js
@@ -178,15 +178,12 @@ export class UtilRegistry {
         util: util,
         index: index,
       }))
-      .filter((activeUtil) => activeUtil.util.name === name)
+      .filter((activeUtil) => activeUtil.util.util.name === name)
       .forEach((activeUtil) => {
         // destroy util instance
-        activeUtil.util.destroy();
-        delete this._activeUtilInstancesWrapped[activeUtil.index];
+        activeUtil.util.instance.destroy();
+        this._activeUtilInstancesWrapped = this._activeUtilInstancesWrapped.splice(activeUtil.index, 1);
       });
-
-    // get rid of now empty array slots
-    this._activeUtilInstancesWrapped = this._activeUtilInstancesWrapped.filter((util) => !!util);
   }
 }
 
diff --git a/frontend/src/services/util-registry/util-registry.spec.js b/frontend/src/services/util-registry/util-registry.spec.js
index 07b9e2627..00f8806b3 100644
--- a/frontend/src/services/util-registry/util-registry.spec.js
+++ b/frontend/src/services/util-registry/util-registry.spec.js
@@ -24,24 +24,6 @@ describe('UtilRegistry', () => {
     });
   });
 
-  describe('deregister()', () => {
-    it('should remove util', () => {
-      // register util
-      utilRegistry.register(TestUtil1);
-      let foundUtil = utilRegistry.find(TestUtil1.name);
-      expect(foundUtil).toBeTruthy();
-
-      // deregister util
-      utilRegistry.deregister(TestUtil1.name);
-      foundUtil = utilRegistry.find(TestUtil1.name);
-      expect(foundUtil).toBeFalsy();
-    });
-
-    it('should destroy util instances if requested', () => {
-      pending('TBD');
-    });
-  });
-
   describe('setup()', () => {
 
     it('should catch errors thrown by the utility', () => {
@@ -107,6 +89,51 @@ describe('UtilRegistry', () => {
     });
   });
 
+  describe('deregister()', () => {
+    let testScope;
+    let testElement1;
+    let testElement2;
+
+    beforeEach(() => {
+      testScope = document.createElement('div');
+      testElement1 = document.createElement('div');
+      testElement2 = document.createElement('div');
+      testElement1.classList.add('util1');
+      testElement2.classList.add('util1');
+      testScope.appendChild(testElement1);
+      testScope.appendChild(testElement2);
+    });
+
+    it('should remove util', () => {
+      // register util
+      utilRegistry.register(TestUtil1);
+      let foundUtil = utilRegistry.find(TestUtil1.name);
+      expect(foundUtil).toBeTruthy();
+
+      // deregister util
+      utilRegistry.deregister(TestUtil1.name);
+      foundUtil = utilRegistry.find(TestUtil1.name);
+      expect(foundUtil).toBeFalsy();
+    });
+
+    it('should destroy util instances if requested', () => {
+      utilRegistry.register(TestUtil1);
+      let foundUtil = utilRegistry.find(TestUtil1.name);
+      expect(foundUtil).toBeTruthy();
+
+      utilRegistry.setup(TestUtil1, testScope);
+      let firstActiveUtil = utilRegistry._activeUtilInstancesWrapped[0];
+      expect(utilRegistry._activeUtilInstancesWrapped.length).toEqual(2);
+      expect(utilRegistry._activeUtilInstancesWrapped[0].element).toEqual(testElement1);
+
+      spyOn(firstActiveUtil.instance, 'destroy');
+
+      utilRegistry.deregister(TestUtil1.name, true);
+      expect(utilRegistry._activeUtilInstancesWrapped[0]).toBeFalsy();
+      expect(firstActiveUtil.instance.destroy).toHaveBeenCalled();
+    });
+  });
+
   describe('initAll()', () => {
     it('should setup all the utilities', () => {
       spyOn(utilRegistry, 'setup');
@@ -181,6 +208,8 @@ class TestUtil1 {
     this.element = element;
     this.app = app;
   }
+
+  destroy() {}
 }
 
 @Utility({ selector: '#util2' })