Fixes #4465 by adding the missing extras folders.

MediaBrowser.Controller/Entities/BaseItem.cs

@@ -87,6 +87,8 @@ namespace MediaBrowser.Controller.Entities
         public const string InterviewFolderName = "interviews";
         public const string SceneFolderName = "scenes";
         public const string SampleFolderName = "samples";
+        public const string ShortsFolderName = "shorts";
+        public const string FeaturettesFolderName = "featurettes";
 
         public static readonly string[] AllExtrasTypesFolderNames = {
             ExtrasFolderName,
@@ -94,7 +96,9 @@ namespace MediaBrowser.Controller.Entities
             DeletedScenesFolderName,
             InterviewFolderName,
             SceneFolderName,
-            SampleFolderName
+            SampleFolderName,
+            ShortsFolderName,
+            FeaturettesFolderName
         };
 
         [JsonIgnore]