1 files changed, 6 insertions, 3 deletions
diff --git a/Emby.Server.Implementations/Library/Resolvers/Books/BookResolver.cs b/Emby.Server.Implementations/Library/Resolvers/Books/BookResolver.cs
index 86a5d8b7d..68076730b 100644
--- a/Emby.Server.Implementations/Library/Resolvers/Books/BookResolver.cs
+++ b/Emby.Server.Implementations/Library/Resolvers/Books/BookResolver.cs
@@ -1,3 +1,5 @@
+#nullable disable
+
 #pragma warning disable CS1591
 
 using System;
@@ -11,9 +13,9 @@ namespace Emby.Server.Implementations.Library.Resolvers.Books
 {
     public class BookResolver : MediaBrowser.Controller.Resolvers.ItemResolver<Book>
     {
-        private readonly string[] _validExtensions = { ".azw", ".azw3", ".cb7", ".cbr", ".cbt", ".cbz", ".epub", ".mobi", ".opf", ".pdf" };
+        private readonly string[] _validExtensions = { ".azw", ".azw3", ".cb7", ".cbr", ".cbt", ".cbz", ".epub", ".mobi", ".pdf" };
 
-        protected override Book Resolve(ItemResolveArgs args)
+        public override Book Resolve(ItemResolveArgs args)
         {
             var collectionType = args.GetCollectionType();
 
@@ -50,7 +52,8 @@ namespace Emby.Server.Implementations.Library.Resolvers.Books
                 var fileExtension = Path.GetExtension(f.FullName) ??
                                     string.Empty;
 
-                return _validExtensions.Contains(fileExtension,
+                return _validExtensions.Contains(
+                    fileExtension,
                                                 StringComparer
                                                     .OrdinalIgnoreCase);
             }).ToList();