diff --git a/dom/indexedDB/ActorsParent.cpp b/dom/indexedDB/ActorsParent.cpp
index fb18c1f96aa1..f051bb08129b 100644
--- a/dom/indexedDB/ActorsParent.cpp
+++ b/dom/indexedDB/ActorsParent.cpp
@@ -9451,7 +9451,7 @@ nsresult DatabaseConnection::CommitWriteTransaction() {
 void DatabaseConnection::RollbackWriteTransaction() {
   AssertIsOnConnectionThread();
   MOZ_ASSERT(!mInReadTransaction);
-  MOZ_ASSERT(mStorageConnection);
+  MOZ_DIAGNOSTIC_ASSERT(mStorageConnection);
 
   AUTO_PROFILER_LABEL("DatabaseConnection::RollbackWriteTransaction", DOM);
 
@@ -10063,6 +10063,13 @@ nsresult DatabaseConnection::AutoSavepoint::Start(
   MOZ_ASSERT(connection);
   connection->AssertIsOnConnectionThread();
 
+  // This is just a quick fix for preventing accessing the nullptr. The cause is
+  // probably because the connection was unexpectedly closed.
+  if (!connection->GetUpdateRefcountFunction()) {
+    NS_WARNING("The connection was closed for some reasons!");
+    return NS_ERROR_DOM_INDEXEDDB_UNKNOWN_ERR;
+  }
+
   MOZ_ASSERT(!mConnection);
   MOZ_ASSERT(!mDEBUGTransaction);