diff --git a/src/renderers/dom/fiber/ReactDOMFiberComponent.js b/src/renderers/dom/fiber/ReactDOMFiberComponent.js
index a98800329222b..137bba92d5aba 100644
--- a/src/renderers/dom/fiber/ReactDOMFiberComponent.js
+++ b/src/renderers/dom/fiber/ReactDOMFiberComponent.js
@@ -298,6 +298,14 @@ function setInitialDOMProperties(
         ensureListeningTo(rootContainerElement, propKey);
       }
     } else if (isCustomComponentTag) {
+      /* Suggested fix?
+       *
+       * if ((DOMProperty.getPropertyInfo(propKey))) {
+       *   DOMPropertyOperations.setValueForProperty(domElement, propKey, nextProp);
+       * } else {
+       *   DOMPropertyOperations.setValueForAttribute(domElement, propKey, nextProp);
+       * }
+      */
       DOMPropertyOperations.setValueForAttribute(domElement, propKey, nextProp);
     } else if (nextProp != null) {
       // If we're updating to null or undefined, we should remove the property
diff --git a/src/renderers/dom/shared/__tests__/DOMPropertyOperations-test.js b/src/renderers/dom/shared/__tests__/DOMPropertyOperations-test.js
index 7f544506a5f35..87ad4a280891f 100644
--- a/src/renderers/dom/shared/__tests__/DOMPropertyOperations-test.js
+++ b/src/renderers/dom/shared/__tests__/DOMPropertyOperations-test.js
@@ -113,6 +113,18 @@ describe('DOMPropertyOperations', () => {
       ReactDOM.render(<div hidden={false} />, container);
       expect(container.firstChild.hasAttribute('hidden')).toBe(false);
     });
+
+    it('should set the className to a custom component', () => {
+      var container = document.createElement('div');
+      ReactDOM.render(<amp className="just-a-class" />, container);
+      expect(container.firstChild.getAttribute('class')).toEqual('just-a-class');
+    });
+
+    it('should set the className to a custom component with a dash on its name', () => {
+      var container = document.createElement('div');
+      ReactDOM.render(<amp-img className="just-a-class" />, container);
+      expect(container.firstChild.getAttribute('class')).toEqual('just-a-class');
+    });
   });
 
   describe('value mutation method', function() {