From 738eccb99db740fd519dea270fb73c92135ed40a Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Thu, 25 Sep 2025 11:00:18 +0000
Subject: [PATCH] Enable hot reloading for Blazor inside an iframe

Co-authored-by: javiercn <6995051+javiercn@users.noreply.github.com>
---
 .../BrowserRefreshMiddleware.cs               |  2 ++
 .../BrowserRefreshMiddlewareTest.cs           | 24 +++++++++++++++++++
 2 files changed, 26 insertions(+)

diff --git a/src/BuiltInTools/BrowserRefresh/BrowserRefreshMiddleware.cs b/src/BuiltInTools/BrowserRefresh/BrowserRefreshMiddleware.cs
index 853b52a83778..16d262a0d1ad 100644
--- a/src/BuiltInTools/BrowserRefresh/BrowserRefreshMiddleware.cs
+++ b/src/BuiltInTools/BrowserRefresh/BrowserRefreshMiddleware.cs
@@ -170,6 +170,8 @@ internal static bool IsBrowserDocumentRequest(HttpContext context)
             if (request.Headers.TryGetValue("Sec-Fetch-Dest", out var values) &&
                 !StringValues.IsNullOrEmpty(values) &&
                 !string.Equals(values[0], "document", StringComparison.OrdinalIgnoreCase) &&
+                !string.Equals(values[0], "frame", StringComparison.OrdinalIgnoreCase) &&
+                !string.Equals(values[0], "iframe", StringComparison.OrdinalIgnoreCase) &&
                 !IsProgressivelyEnhancedNavigation(context.Request))
             {
                 // See https://github.com/dotnet/aspnetcore/issues/37326.
diff --git a/test/Microsoft.AspNetCore.Watch.BrowserRefresh.Tests/BrowserRefreshMiddlewareTest.cs b/test/Microsoft.AspNetCore.Watch.BrowserRefresh.Tests/BrowserRefreshMiddlewareTest.cs
index 1fa4b862b693..ba144b2c3296 100644
--- a/test/Microsoft.AspNetCore.Watch.BrowserRefresh.Tests/BrowserRefreshMiddlewareTest.cs
+++ b/test/Microsoft.AspNetCore.Watch.BrowserRefresh.Tests/BrowserRefreshMiddlewareTest.cs
@@ -182,6 +182,30 @@ public void IsBrowserDocumentRequest_ReturnsTrue_IfRequestFetchMetadataRequestHe
         [Theory]
         [InlineData("frame")]
         [InlineData("iframe")]
+        public void IsBrowserDocumentRequest_ReturnsTrue_IfRequestFetchMetadataRequestHeaderIsFrame(string headerValue)
+        {
+            // Arrange
+            var context = new DefaultHttpContext
+            {
+                Request =
+                {
+                    Method = "Post",
+                    Headers =
+                    {
+                        ["Accept"] = "text/html",
+                        ["Sec-Fetch-Dest"] = headerValue,
+                    },
+                },
+            };
+
+            // Act
+            var result = BrowserRefreshMiddleware.IsBrowserDocumentRequest(context);
+
+            // Assert
+            Assert.True(result);
+        }
+
+        [Theory]
         [InlineData("serviceworker")]
         public void IsBrowserDocumentRequest_ReturnsFalse_IfRequestFetchMetadataRequestHeaderIsNotDocument(string headerValue)
         {