--- a/dom/base/nsContentPermissionHelper.h
+++ b/dom/base/nsContentPermissionHelper.h
@@ -132,16 +132,17 @@ class ContentPermissionRequestBase : pub
     Allow,
     Deny,
     Request,
   };
   void RequestDelayedTask(nsIEventTarget* aTarget, DelayedTaskType aType);
 
  protected:
   // @param aPrefName see `mPrefName`.
+  // @param aType see `mType`.
   ContentPermissionRequestBase(nsIPrincipal* aPrincipal,
                                nsPIDOMWindowInner* aWindow,
                                const nsACString& aPrefName,
                                const nsACString& aType);
   virtual ~ContentPermissionRequestBase() = default;
 
   nsCOMPtr<nsIPrincipal> mPrincipal;
   nsCOMPtr<nsIPrincipal> mTopLevelPrincipal;
@@ -150,17 +151,20 @@ class ContentPermissionRequestBase : pub
 
   // The prefix of a pref which allows tests to bypass showing the prompt.
   // Tests will have to set both of
   // ${mPrefName}.prompt.testing and
   // ${mPrefName}.prompt.testing.allow
   // to either true or false. If no such testing is required, mPrefName may be
   // empty.
   const nsCString mPrefName;
+
+  // The type of the request, such as "autoplay-media-audible".
   const nsCString mType;
+
   bool mIsHandlingUserInput;
   bool mMaybeUnsafePermissionDelegate;
 };
 
 }  // namespace dom
 }  // namespace mozilla
 
 using mozilla::dom::ContentPermissionRequestParent;