New json converter implemented.

Emby.Server.Implementations/Plugins/PluginManager.cs

@@ -9,6 +9,7 @@ using System.Text.Json;
 using MediaBrowser.Common;
 using MediaBrowser.Common.Extensions;
 using MediaBrowser.Common.Json;
+using MediaBrowser.Common.Json.Converters;
 using MediaBrowser.Common.Plugins;
 using MediaBrowser.Model.Configuration;
 using MediaBrowser.Model.Plugins;
@@ -50,6 +51,7 @@ namespace Emby.Server.Implementations.Plugins
             _pluginsPath = pluginsPath;
             _appVersion = appVersion ?? throw new ArgumentNullException(nameof(appVersion));
             _jsonOptions = JsonDefaults.GetOptions();
+            _jsonOptions.Converters.Add(new JsonGuidDashConverter());
             _jsonOptions.WriteIndented = true;
             _config = config;
             _appHost = appHost;

MediaBrowser.Common/Json/Converters/JsonGuidDashConverter.cs

@@ -0,0 +1,26 @@
+using System;
+using System.Globalization;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+namespace MediaBrowser.Common.Json.Converters
+{
+    /// <summary>
+    /// Converts a GUID object or value to/from JSON.
+    /// </summary>
+    public class JsonGuidDashConverter : JsonConverter<Guid>
+    {
+        /// <inheritdoc />
+        public override Guid Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
+        {
+            var guidStr = reader.GetString();
+            return guidStr == null ? Guid.Empty : new Guid(guidStr);
+        }
+
+        /// <inheritdoc />
+        public override void Write(Utf8JsonWriter writer, Guid value, JsonSerializerOptions options)
+        {
+            writer.WriteStringValue(value.ToString());
+        }
+    }
+}

MediaBrowser.Common/Plugins/PluginManifest.cs

@@ -1,6 +1,7 @@
 #nullable enable
 using System;
 using System.Text.Json.Serialization;
+using MediaBrowser.Common.Json.Converters;
 using MediaBrowser.Model.Plugins;
 
 namespace MediaBrowser.Common.Plugins
@@ -32,6 +33,7 @@ namespace MediaBrowser.Common.Plugins
         /// Gets or sets the Global Unique Identifier for the plugin.
         /// </summary>
         [JsonPropertyName("guid")]
+        [JsonConverter(typeof(JsonGuidDashConverter))]
         public Guid Id { get; set; }
 
         /// <summary>