diff --git a/server/initializers/constants.ts b/server/initializers/constants.ts
index 032f63c8f..e4b8a8eca 100644
--- a/server/initializers/constants.ts
+++ b/server/initializers/constants.ts
@@ -790,7 +790,6 @@ function buildVideoMimetypeExt () {
         'video/x-msvideo': '.avi',
         'video/x-flv': '.flv',
         'video/x-matroska': '.mkv',
-        'application/octet-stream': '.mkv',
         'video/avi': '.avi',
         'video/x-m4v': '.m4v',
         'video/m4v': '.m4v'