diff --git a/src/GregModmanager.Core/Models/AppJsonContext.cs b/src/GregModmanager.Core/Models/AppJsonContext.cs
index d7fe96d..8a3cc3c 100644
--- a/src/GregModmanager.Core/Models/AppJsonContext.cs
+++ b/src/GregModmanager.Core/Models/AppJsonContext.cs
@@ -34,6 +34,7 @@ namespace GregModmanager.Models;
 [JsonSerializable(typeof(int))]
 [JsonSerializable(typeof(RalphTaskStatus))]
 [JsonSerializable(typeof(AssetModMetadata))]
+[JsonSerializable(typeof(object))]
 public partial class AppJsonContext : JsonSerializerContext
 {
 }
diff --git a/src/GregModmanager.Core/Services/BetaPluginSource.cs b/src/GregModmanager.Core/Services/BetaPluginSource.cs
index 3970159..b45d023 100644
--- a/src/GregModmanager.Core/Services/BetaPluginSource.cs
+++ b/src/GregModmanager.Core/Services/BetaPluginSource.cs
@@ -1,51 +1,52 @@
-using System.Text.Json;
-using GregModmanager.Models;
-
-namespace GregModmanager.Services;
-
-/// <summary>
-/// Beta distribution channel served from a custom backend.
-/// Configure base URL via Preferences.
-/// </summary>
-public sealed class BetaPluginSource : IgregPluginChannelSource
-{
-	/// <summary>Preferences key for the beta server base URL.</summary>
-	public const string PrefKeyBetaServerUrl = "greg_beta_server_url";
-
-	private static readonly HttpClient _http = new();
-
-	public string ChannelName => "beta";
-
-	public IReadOnlyList<PluginPackageInfo> ListPlugins()
-	{
-#if WINDOWS || ANDROID || IOS || MACCATALYST
-		var url = Preferences.Default.Get(PrefKeyBetaServerUrl, string.Empty);
-#else
-		var url = "";
-#endif
-		if (string.IsNullOrWhiteSpace(url))
-		{
-			throw new InvalidOperationException(
-				"Beta-Kanal: Server-URL ist noch nicht konfiguriert. " +
-				"Setze die URL unter Einstellungen (Preferences-Key: greg_beta_server_url).");
-		}
-
-		var endpoint = url.TrimEnd('/') + "/api/plugins";
-
-		try
-		{
-			var response = _http.GetAsync(endpoint).GetAwaiter().GetResult();
-			response.EnsureSuccessStatusCode();
-
-			var json = response.Content.ReadAsStringAsync().GetAwaiter().GetResult();
-
-			var plugins = JsonSerializer.Deserialize(json, AppJsonContext.Default.ListPluginPackageInfo);
-
-			return plugins ?? new List<PluginPackageInfo>();
-		}
-		catch (Exception ex)
-		{
-			throw new InvalidOperationException($"Beta-Kanal: Fehler beim Abrufen der Plugins (URL: {endpoint}). Details: {ex.Message}", ex);
-		}
-	}
-}
+using System.Text.Json;
+using GregModmanager.Models;
+using GregModmanager.Localization;
+using System.Collections.Generic;
+using System.Net.Http;
+using System;
+
+namespace GregModmanager.Services;
+
+/// <summary>
+/// Beta distribution channel served from a custom backend.
+/// Configure base URL via Preferences.
+/// </summary>
+public sealed class BetaPluginSource : IgregPluginChannelSource
+{
+	/// <summary>Preferences key for the beta server base URL.</summary>
+	public const string PrefKeyBetaServerUrl = "greg_beta_server_url";
+
+	private static readonly HttpClient _http = new();
+
+	public string ChannelName => "beta";
+
+	public IReadOnlyList<PluginPackageInfo> ListPlugins()
+	{
+		var url = S.Preferences.GetString(PrefKeyBetaServerUrl, string.Empty);
+		if (string.IsNullOrWhiteSpace(url))
+		{
+			throw new InvalidOperationException(
+				"Beta-Kanal: Server-URL ist noch nicht konfiguriert. " +
+				"Setze die URL unter Einstellungen (Preferences-Key: greg_beta_server_url).");
+		}
+
+		var endpoint = url.TrimEnd('/') + "/api/plugins";
+
+		try
+		{
+			using var request = new HttpRequestMessage(HttpMethod.Get, endpoint);
+			using var response = _http.Send(request);
+			response.EnsureSuccessStatusCode();
+
+			using var stream = response.Content.ReadAsStream();
+
+			var plugins = JsonSerializer.Deserialize(stream, AppJsonContext.Default.ListPluginPackageInfo);
+
+			return plugins ?? new List<PluginPackageInfo>();
+		}
+		catch (Exception ex)
+		{
+			throw new InvalidOperationException($"Beta-Kanal: Fehler beim Abrufen der Plugins (URL: {endpoint}). Details: {ex.Message}", ex);
+		}
+	}
+}
diff --git a/src/GregModmanager.Core/Services/TelemetryService.cs b/src/GregModmanager.Core/Services/TelemetryService.cs
index 8531b66..0c3f72c 100644
--- a/src/GregModmanager.Core/Services/TelemetryService.cs
+++ b/src/GregModmanager.Core/Services/TelemetryService.cs
@@ -99,7 +99,7 @@ public async Task TrackEventAsync(string eventName, object payload, Dictionary<s
         var message = payload switch
         {
             SyncCollectionEvent sync => JsonSerializer.Serialize(sync, AppJsonContext.Default.SyncCollectionEvent),
-            _ => JsonSerializer.Serialize(payload, payload.GetType(), AppJsonContext.Default.Options)
+            _ => JsonSerializer.Serialize(payload, AppJsonContext.Default.Object)
         };
 
         await PushToLokiAsync(eventName, message, labels);
diff --git a/tests/GregModmanager.Tests/BetaPluginSourceTests.cs b/tests/GregModmanager.Tests/BetaPluginSourceTests.cs
new file mode 100644
index 0000000..944d745
--- /dev/null
+++ b/tests/GregModmanager.Tests/BetaPluginSourceTests.cs
@@ -0,0 +1,50 @@
+using System;
+using Xunit;
+using GregModmanager.Services;
+using GregModmanager.Localization;
+using System.Collections.Generic;
+
+namespace GregModmanager.Tests;
+
+public class BetaPluginSourceTests
+{
+    private class MockPreferences : IPreferences
+    {
+        private readonly Dictionary<string, object> _data = new();
+
+        public string GetString(string key, string defaultValue) => _data.TryGetValue(key, out var val) && val is string s ? s : defaultValue;
+        public bool GetBool(string key, bool defaultValue) => _data.TryGetValue(key, out var val) && val is bool b ? b : defaultValue;
+        public int GetInt(string key, int defaultValue) => _data.TryGetValue(key, out var val) && val is int i ? i : defaultValue;
+
+        public void SetString(string key, string value) => _data[key] = value;
+        public void SetBool(string key, bool value) => _data[key] = value;
+        public void SetInt(string key, int value) => _data[key] = value;
+        public void Remove(string key) => _data.Remove(key);
+    }
+
+    [Fact]
+    public void ListPlugins_ThrowsWhenUrlNotConfigured()
+    {
+        var mockPrefs = new MockPreferences();
+        S.Preferences = mockPrefs;
+
+        var source = new BetaPluginSource();
+
+        var ex = Assert.Throws<InvalidOperationException>(() => source.ListPlugins());
+        Assert.Contains("Server-URL ist noch nicht konfiguriert", ex.Message);
+    }
+
+    [Fact]
+    public void ListPlugins_ThrowsWhenUrlIsInvalidOrEndpointFails()
+    {
+        var mockPrefs = new MockPreferences();
+        mockPrefs.SetString(BetaPluginSource.PrefKeyBetaServerUrl, "http://localhost:12345/invalid");
+        S.Preferences = mockPrefs;
+
+        var source = new BetaPluginSource();
+
+        var ex = Assert.Throws<InvalidOperationException>(() => source.ListPlugins());
+        Assert.Contains("Fehler beim Abrufen der Plugins", ex.Message);
+        Assert.Contains("http://localhost:12345/invalid/api/plugins", ex.Message);
+    }
+}