fix

src/server/service/search-delegator/elasticsearch.js

@@ -389,6 +389,7 @@ class ElasticsearchDelegator {
         { path: 'creator', model: 'User', select: 'username' },
         { path: 'revision', model: 'Revision', select: 'body' },
       ])
+      .lean()
       .cursor();
 
     let skipped = 0;