diff --git a/dom/html/ImageDocument.cpp b/dom/html/ImageDocument.cpp
index bfebbc75f40..46adb9af10b 100644
--- a/dom/html/ImageDocument.cpp
+++ b/dom/html/ImageDocument.cpp
@@ -66,9 +66,9 @@ ImageListener::~ImageListener() = default;
 
 NS_IMETHODIMP
 ImageListener::OnStartRequest(nsIRequest* request) {
-  NS_ENSURE_TRUE(mDocument, NS_ERROR_FAILURE);
+  RefPtr<ImageDocument> imgDoc = static_cast<ImageDocument*>(mDocument.get());
+  NS_ENSURE_TRUE(imgDoc, NS_ERROR_FAILURE);
 
-  ImageDocument* imgDoc = static_cast<ImageDocument*>(mDocument.get());
   nsCOMPtr<nsIChannel> channel = do_QueryInterface(request);
   if (!channel) {
     return NS_ERROR_FAILURE;
diff --git a/dom/html/MediaDocument.cpp b/dom/html/MediaDocument.cpp
index 990e7de4895..5e29d6863e6 100644
--- a/dom/html/MediaDocument.cpp
+++ b/dom/html/MediaDocument.cpp
@@ -41,9 +41,10 @@ NS_IMPL_ISUPPORTS(MediaDocumentStreamListener, nsIRequestObserver,
 
 NS_IMETHODIMP
 MediaDocumentStreamListener::OnStartRequest(nsIRequest* request) {
-  NS_ENSURE_TRUE(mDocument, NS_ERROR_FAILURE);
+  RefPtr<MediaDocument> document = mDocument;
+  NS_ENSURE_TRUE(document, NS_ERROR_FAILURE);
 
-  mDocument->StartLayout();
+  document->StartLayout();
 
   if (nsCOMPtr<nsIStreamListener> nextStream = mNextStream) {
     return nextStream->OnStartRequest(request);