diff --git a/packages/model-viewer/src/features/controls.ts b/packages/model-viewer/src/features/controls.ts
index e41daf21f7..6b9b41bb30 100644
--- a/packages/model-viewer/src/features/controls.ts
+++ b/packages/model-viewer/src/features/controls.ts
@@ -888,11 +888,7 @@ export const ControlsMixin = <T extends Constructor<ModelViewerElementBase>>(
     };
 
     [$onPointerChange] = (event: PointerChangeEvent) => {
-      if (event.type === 'pointer-change-start') {
-        this[$container].classList.add('pointer-tumbling');
-      } else {
-        this[$container].classList.remove('pointer-tumbling');
-      }
+      this[$container].classList.toggle('pointer-tumbling', event.type === 'pointer-change-start');
     };
   }
 
diff --git a/packages/model-viewer/src/features/loading.ts b/packages/model-viewer/src/features/loading.ts
index 4b10845d47..8d2b7fafef 100644
--- a/packages/model-viewer/src/features/loading.ts
+++ b/packages/model-viewer/src/features/loading.ts
@@ -295,14 +295,7 @@ export const LoadingMixin = <T extends Constructor<ModelViewerElementBase>>(
           parentNode.appendChild(this[$defaultProgressBarElement]);
         }
 
-        // NOTE(cdata): IE11 does not properly respect the second parameter
-        // of classList.toggle, which this implementation originally used.
-        // @see https://developer.microsoft.com/en-us/microsoft-edge/platform/issues/11865865/
-        if (progress === 1.0) {
-          this[$defaultProgressBarElement].classList.add('hide');
-        } else {
-          this[$defaultProgressBarElement].classList.remove('hide');
-        }
+        this[$defaultProgressBarElement].classList.toggle('hide', progress === 1.0);
       });
     }, PROGRESS_BAR_UPDATE_THRESHOLD);
 
diff --git a/packages/model-viewer/src/styles/deserializers.ts b/packages/model-viewer/src/styles/deserializers.ts
index ecf9757969..b2f403b2de 100644
--- a/packages/model-viewer/src/styles/deserializers.ts
+++ b/packages/model-viewer/src/styles/deserializers.ts
@@ -47,13 +47,7 @@ export const enumerationDeserializer = <T extends string>(allowedNames: T[]) =>
                           .map(valueNode => valueNode.value as T)
                           .filter(name => allowedNames.indexOf(name) > -1);
 
-        // NOTE(cdata): IE11 does not support constructing a Set directly from
-        // an iterable, so we need to manually add all the items:
-        const result = new Set<T>();
-        for (const name of names) {
-          result.add(name);
-        }
-        return result;
+        return new Set<T>(names);
       } catch (_error) {
       }
       return new Set();
diff --git a/packages/model-viewer/src/three-components/Hotspot.ts b/packages/model-viewer/src/three-components/Hotspot.ts
index f20d7ee766..7569589867 100644
--- a/packages/model-viewer/src/three-components/Hotspot.ts
+++ b/packages/model-viewer/src/three-components/Hotspot.ts
@@ -175,12 +175,7 @@ export class Hotspot extends CSS2DObject {
   }
 
   updateVisibility(show: boolean) {
-    // NOTE: IE11 doesn't support a second arg for classList.toggle
-    if (show) {
-      this.element.classList.remove('hide');
-    } else {
-      this.element.classList.add('hide');
-    }
+    this.element.classList.toggle('hide', !show);
 
     // NOTE: ShadyDOM doesn't support slot.assignedElements, otherwise we could
     // use that here.
@@ -196,12 +191,7 @@ export class Hotspot extends CSS2DObject {
       if (visibilityAttribute != null) {
         const attributeName = `data-${visibilityAttribute}`;
 
-        // NOTE: IE11 doesn't support toggleAttribute
-        if (show) {
-          element.setAttribute(attributeName, '');
-        } else {
-          element.removeAttribute(attributeName);
-        }
+        element.toggleAttribute(attributeName, show);
       }
 
       element.dispatchEvent(new CustomEvent('hotspot-visibility', {
diff --git a/packages/model-viewer/src/utilities.ts b/packages/model-viewer/src/utilities.ts
index 6d937531bb..467653308a 100644
--- a/packages/model-viewer/src/utilities.ts
+++ b/packages/model-viewer/src/utilities.ts
@@ -206,34 +206,6 @@ export const isDebugMode = (() => {
 })();
 
 
-/**
- * Returns the first key in a Map in iteration order.
- *
- * NOTE(cdata): This is necessary because IE11 does not implement iterator
- * methods of Map, and polymer-build does not polyfill these methods for
- * compatibility and performance reasons. This helper proposes that it is
- * a reasonable compromise to sacrifice a very small amount of runtime
- * performance in IE11 for the sake of code clarity.
- */
-export const getFirstMapKey = <T = any, U = any>(map: Map<T, U>): T|null => {
-  if (map.keys != null) {
-    return map.keys().next().value || null;
-  }
-
-  let firstKey: T|null = null;
-
-  try {
-    map.forEach((_value: U, key: T, _map: Map<T, U>) => {
-      firstKey = key;
-      // Stop iterating the Map with forEach:
-      throw new Error();
-    });
-  } catch (_error) {
-  }
-
-  return firstKey;
-};
-
 /**
  * Three.js EventDispatcher and DOM EventTarget use different event patterns,
  * so AnyEvent covers the shape of both event types.