diff --git a/lib/reducers/message-reducer.js b/lib/reducers/message-reducer.js
--- a/lib/reducers/message-reducer.js
+++ b/lib/reducers/message-reducer.js
@@ -1311,14 +1311,6 @@
       `message ${id} did not contain media with ID ${currentMediaID}`,
     );
 
-    const updatedMessageStore = {
-      ...messageStore,
-      messages: {
-        ...messageStore.messages,
-        [id]: updatedMessage,
-      },
-    };
-
     const messageStoreOperations = [
       {
         type: 'replace',
@@ -1334,13 +1326,13 @@
       messageStoreOperations,
     );
 
-    assertMessageStoreMessagesAreEqual(
-      processedMessageStore,
-      updatedMessageStore,
-      action.type,
-    );
-
-    return { messageStoreOperations, messageStore: updatedMessageStore };
+    return {
+      messageStoreOperations,
+      messageStore: {
+        ...messageStore,
+        messages: processedMessageStore.messages,
+      },
+    };
   } else if (action.type === createLocalMessageActionType) {
     const messageInfo = ensureRealizedThreadIDIsUsedWhenPossible(
       action.payload,