diff --git a/dom/html/HTMLFormElement.cpp b/dom/html/HTMLFormElement.cpp
index e4172bc81f36..36aad32c7cba 100644
--- a/dom/html/HTMLFormElement.cpp
+++ b/dom/html/HTMLFormElement.cpp
@@ -1756,37 +1756,37 @@ nsGenericHTMLFormElement* HTMLFormElement::GetDefaultSubmitElement() const {
 }
 
 bool HTMLFormElement::IsDefaultSubmitElement(
-    const nsIFormControl* aControl) const {
-  MOZ_ASSERT(aControl, "Unexpected call");
+    const nsGenericHTMLFormElement* aElement) const {
+  MOZ_ASSERT(aElement, "Unexpected call");
 
-  if (aControl == mDefaultSubmitElement) {
+  if (aElement == mDefaultSubmitElement) {
     // Yes, it is
     return true;
   }
 
-  if (mDefaultSubmitElement || (aControl != mFirstSubmitInElements &&
-                                aControl != mFirstSubmitNotInElements)) {
+  if (mDefaultSubmitElement || (aElement != mFirstSubmitInElements &&
+                                aElement != mFirstSubmitNotInElements)) {
     // It isn't
     return false;
   }
 
   // mDefaultSubmitElement is null, but we have a non-null submit around
-  // (aControl, in fact).  figure out whether it's in fact the default submit
+  // (aElement, in fact).  figure out whether it's in fact the default submit
   // and just hasn't been set that way yet.  Note that we can't just call
   // HandleDefaultSubmitRemoval because we might need to notify to handle that
   // correctly and we don't know whether that's safe right here.
   if (!mFirstSubmitInElements || !mFirstSubmitNotInElements) {
-    // We only have one first submit; aControl has to be it
+    // We only have one first submit; aElement has to be it
     return true;
   }
 
   // We have both kinds of submits.  Check which comes first.
-  nsIFormControl* defaultSubmit =
+  nsGenericHTMLFormElement* defaultSubmit =
       CompareFormControlPosition(mFirstSubmitInElements,
                                  mFirstSubmitNotInElements, this) < 0
           ? mFirstSubmitInElements
           : mFirstSubmitNotInElements;
-  return aControl == defaultSubmit;
+  return aElement == defaultSubmit;
 }
 
 bool HTMLFormElement::ImplicitSubmissionIsDisabled() const {
diff --git a/dom/html/HTMLFormElement.h b/dom/html/HTMLFormElement.h
index 0b54b22e8dfa..031198ad7235 100644
--- a/dom/html/HTMLFormElement.h
+++ b/dom/html/HTMLFormElement.h
@@ -207,13 +207,13 @@ class HTMLFormElement final : public nsGenericHTMLElement,
   bool IsLastActiveElement(const nsIFormControl* aControl) const;
 
   /**
-   * Check whether a given nsIFormControl is the default submit
+   * Check whether a given nsGenericHTMLFormElement is the default submit
    * element.  This is different from just comparing to
    * GetDefaultSubmitElement() in certain situations inside an update
-   * when GetDefaultSubmitElement() might not be up to date.  aControl
+   * when GetDefaultSubmitElement() might not be up to date. aElement
    * is expected to not be null.
    */
-  bool IsDefaultSubmitElement(const nsIFormControl* aControl) const;
+  bool IsDefaultSubmitElement(const nsGenericHTMLFormElement* aElement) const;
 
   /**
    * Flag the form to know that a button or image triggered scripted form