diff --git a/manifest.json b/manifest.json
index 3f3c0303..323feab3 100644
--- a/manifest.json
+++ b/manifest.json
@@ -84,8 +84,7 @@
       "display_name": "A list of observed extensions known to be abused by threat actors in malicious message content.",
       "headers": [
         "entry"
-      ],
-      "format": "hostname"
+      ]
     },
     {
       "file": "file_types_images.txt",