Add missing singleton

Emby.Server.Implementations/ApplicationHost.cs

@@ -57,6 +57,7 @@ using MediaBrowser.Controller.Configuration;
 using MediaBrowser.Controller.Drawing;
 using MediaBrowser.Controller.Dto;
 using MediaBrowser.Controller.Entities;
+using MediaBrowser.Controller.IO;
 using MediaBrowser.Controller.Library;
 using MediaBrowser.Controller.LiveTv;
 using MediaBrowser.Controller.Lyrics;
@@ -508,6 +509,7 @@ namespace Emby.Server.Implementations
 
             serviceCollection.AddSingleton<IMediaEncoder, MediaBrowser.MediaEncoding.Encoder.MediaEncoder>();
             serviceCollection.AddSingleton<EncodingHelper>();
+            serviceCollection.AddSingleton<IPathManager, PathManager>();
 
             // TODO: Refactor to eliminate the circular dependencies here so that Lazy<T> isn't required
             serviceCollection.AddTransient(provider => new Lazy<ILibraryMonitor>(provider.GetRequiredService<ILibraryMonitor>));