diff --git a/src/DataTables.GeneratorCore/TreeTableTemplate.cs b/src/DataTables.GeneratorCore/TreeTableTemplate.cs
index 874bebd..05bd713 100644
--- a/src/DataTables.GeneratorCore/TreeTableTemplate.cs
+++ b/src/DataTables.GeneratorCore/TreeTableTemplate.cs
@@ -29,13 +29,11 @@ public override string TransformText()
     GenerationEnvironment.Clear();
     var text = base.TransformText();
     GenerationEnvironment.Clear();
-    var marker = "    #endregion" + Environment.NewLine + "}";
     var insert = BuildTreeApi();
-    var idx = text.IndexOf(marker, StringComparison.Ordinal);
-    if (idx < 0 && Environment.NewLine != "\n")
+    var idx = text.IndexOf("    #endregion\r\n}", StringComparison.Ordinal);
+    if (idx < 0)
     {
-        marker = "    #endregion\n}";
-        idx = text.IndexOf(marker, StringComparison.Ordinal);
+        idx = text.IndexOf("    #endregion\n}", StringComparison.Ordinal);
     }
     Write(idx < 0 ? text : text.Insert(idx, insert));
 
diff --git a/src/DataTables.GeneratorCore/TreeTableTemplate.tt b/src/DataTables.GeneratorCore/TreeTableTemplate.tt
index 6cdcb56..6bb55f3 100644
--- a/src/DataTables.GeneratorCore/TreeTableTemplate.tt
+++ b/src/DataTables.GeneratorCore/TreeTableTemplate.tt
@@ -8,13 +8,11 @@
     GenerationEnvironment.Clear();
     var text = base.TransformText();
     GenerationEnvironment.Clear();
-    var marker = "    #endregion" + Environment.NewLine + "}";
     var insert = BuildTreeApi();
-    var idx = text.IndexOf(marker, StringComparison.Ordinal);
-    if (idx < 0 && Environment.NewLine != "\n")
+    var idx = text.IndexOf("    #endregion\r\n}", StringComparison.Ordinal);
+    if (idx < 0)
     {
-        marker = "    #endregion\n}";
-        idx = text.IndexOf(marker, StringComparison.Ordinal);
+        idx = text.IndexOf("    #endregion\n}", StringComparison.Ordinal);
     }
     Write(idx < 0 ? text : text.Insert(idx, insert));
 #><#
diff --git a/src/DataTables.Unity/Assets/Tests/StreamingAssetsDataSourceTests.cs b/src/DataTables.Unity/Assets/Tests/StreamingAssetsDataSourceTests.cs
index 83a8144..58c90ec 100644
--- a/src/DataTables.Unity/Assets/Tests/StreamingAssetsDataSourceTests.cs
+++ b/src/DataTables.Unity/Assets/Tests/StreamingAssetsDataSourceTests.cs
@@ -34,14 +34,11 @@ public async Task PackagedManifest_CompletesThroughStreamingAssetsTransport()
         }
 
         [Test]
-        public void MissingResource_MapsToStructuredDataSourceException()
+        public async Task MissingResource_MapsToStructuredDataSourceException()
         {
             var source = new StreamingAssetsDataSource(AppendPath(Application.streamingAssetsPath, "DataTablesTests"));
 
-            var exception = Assert.ThrowsAsync<DataSourceException>(async () =>
-            {
-                await source.OpenReadAsync("Missing", CancellationToken.None);
-            });
+            var exception = await ThrowsAsync<DataSourceException>(() => source.OpenReadAsync("Missing", CancellationToken.None).AsTask());
 
             Assert.That(exception.SourceType, Is.EqualTo(DataSourceType.StreamingAssets));
             Assert.That(exception.Operation, Is.EqualTo(DataSourceOperation.OpenRead));
@@ -51,17 +48,36 @@ public void MissingResource_MapsToStructuredDataSourceException()
 
 #if UNITY_ANDROID || UNITY_WEBGL
         [Test]
-        public void InFlightRequestCancellation_AbortsAndRemainsOperationCanceledException()
+        public async Task InFlightRequestCancellation_AbortsAndRemainsOperationCanceledException()
         {
             using var cancellation = new CancellationTokenSource(TimeSpan.FromSeconds(5));
             var source = new StreamingAssetsDataSource("https://example.invalid/datatables-tests");
             Task pending = source.OpenReadAsync("Never", cancellation.Token).AsTask();
             cancellation.Cancel();
 
-            Assert.ThrowsAsync<OperationCanceledException>(async () => await pending);
+            await ThrowsAsync<OperationCanceledException>(() => pending);
         }
 #endif
 
+        private static async Task<TException> ThrowsAsync<TException>(Func<Task> action)
+            where TException : Exception
+        {
+            try
+            {
+                await action();
+            }
+            catch (TException exception)
+            {
+                return exception;
+            }
+            catch (Exception exception)
+            {
+                throw new AssertionException($"Expected {typeof(TException).Name} but caught {exception.GetType().Name}.");
+            }
+
+            throw new AssertionException($"Expected {typeof(TException).Name} to be thrown.");
+        }
+
         private static string AppendPath(string root, string segment)
             => root.Replace('\\', '/').TrimEnd('/') + "/" + Uri.EscapeDataString(segment);
     }