From 610dfe09f6680cd2c3259a1514e0680b8575e435 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Fri, 13 Feb 2026 18:44:00 +0000
Subject: [PATCH 1/3] Initial plan


From 22e14cf0da7b7e3cec23dbd5f0714cf36a0ee32a Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Fri, 13 Feb 2026 19:11:17 +0000
Subject: [PATCH 2/3] Enable runtime-async for System.IO.Compression and
 System.IO.Compression.Brotli

Co-authored-by: agocke <515774+agocke@users.noreply.github.com>
---
 .../src/System.IO.Compression.Brotli.csproj               | 8 ++++++++
 .../src/System.IO.Compression.csproj                      | 8 ++++++++
 2 files changed, 16 insertions(+)

diff --git a/src/libraries/System.IO.Compression.Brotli/src/System.IO.Compression.Brotli.csproj b/src/libraries/System.IO.Compression.Brotli/src/System.IO.Compression.Brotli.csproj
index 124cd52bc84993..cc442846b767f9 100644
--- a/src/libraries/System.IO.Compression.Brotli/src/System.IO.Compression.Brotli.csproj
+++ b/src/libraries/System.IO.Compression.Brotli/src/System.IO.Compression.Brotli.csproj
@@ -6,6 +6,14 @@
     <UseCompilerGeneratedDocXmlFile>false</UseCompilerGeneratedDocXmlFile>
   </PropertyGroup>
 
+  <PropertyGroup Condition="'$(TargetOS)' != 'browser'
+    and '$(TargetOS)' != 'wasi'
+    and '$(RuntimeFlavor)' != 'Mono'">
+    <EnablePreviewFeatures>true</EnablePreviewFeatures>
+    <Features>$(Features);runtime-async=on</Features>
+    <NoWarn>$(NoWarn);SYSLIB5007</NoWarn>
+  </PropertyGroup>
+
   <!-- DesignTimeBuild requires all the TargetFramework Derived Properties to not be present in the first property group. -->
   <PropertyGroup>
     <TargetPlatformIdentifier>$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)'))</TargetPlatformIdentifier>
diff --git a/src/libraries/System.IO.Compression/src/System.IO.Compression.csproj b/src/libraries/System.IO.Compression/src/System.IO.Compression.csproj
index 91ad2914646cd3..456b249e367ea0 100644
--- a/src/libraries/System.IO.Compression/src/System.IO.Compression.csproj
+++ b/src/libraries/System.IO.Compression/src/System.IO.Compression.csproj
@@ -7,6 +7,14 @@
     <GenAPIExcludeApiList>ReferenceAssemblyExclusions.txt</GenAPIExcludeApiList>
   </PropertyGroup>
 
+  <PropertyGroup Condition="'$(TargetOS)' != 'browser'
+    and '$(TargetOS)' != 'wasi'
+    and '$(RuntimeFlavor)' != 'Mono'">
+    <EnablePreviewFeatures>true</EnablePreviewFeatures>
+    <Features>$(Features);runtime-async=on</Features>
+    <NoWarn>$(NoWarn);SYSLIB5007</NoWarn>
+  </PropertyGroup>
+
   <!-- DesignTimeBuild requires all the TargetFramework Derived Properties to not be present in the first property group. -->
   <PropertyGroup>
     <TargetPlatformIdentifier>$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)'))</TargetPlatformIdentifier>

From 06236ed1d1c9084cc63e34d682acdbe90836a869 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Sat, 14 Feb 2026 00:21:31 +0000
Subject: [PATCH 3/3] Enable runtime-async for System.Net.WebSockets; fix
 preview feature propagation for all three libraries

Co-authored-by: agocke <515774+agocke@users.noreply.github.com>
---
 .../src/System.IO.Compression.Brotli.csproj                | 3 +--
 .../System.IO.Compression/src/System.IO.Compression.csproj | 3 +--
 .../System.Net.WebSockets/src/System.Net.WebSockets.csproj | 7 +++++++
 3 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/src/libraries/System.IO.Compression.Brotli/src/System.IO.Compression.Brotli.csproj b/src/libraries/System.IO.Compression.Brotli/src/System.IO.Compression.Brotli.csproj
index cc442846b767f9..a4ab3c17643994 100644
--- a/src/libraries/System.IO.Compression.Brotli/src/System.IO.Compression.Brotli.csproj
+++ b/src/libraries/System.IO.Compression.Brotli/src/System.IO.Compression.Brotli.csproj
@@ -9,9 +9,8 @@
   <PropertyGroup Condition="'$(TargetOS)' != 'browser'
     and '$(TargetOS)' != 'wasi'
     and '$(RuntimeFlavor)' != 'Mono'">
-    <EnablePreviewFeatures>true</EnablePreviewFeatures>
+    <NoWarn>$(NoWarn);CA2252</NoWarn>
     <Features>$(Features);runtime-async=on</Features>
-    <NoWarn>$(NoWarn);SYSLIB5007</NoWarn>
   </PropertyGroup>
 
   <!-- DesignTimeBuild requires all the TargetFramework Derived Properties to not be present in the first property group. -->
diff --git a/src/libraries/System.IO.Compression/src/System.IO.Compression.csproj b/src/libraries/System.IO.Compression/src/System.IO.Compression.csproj
index 456b249e367ea0..1f01251d6050f6 100644
--- a/src/libraries/System.IO.Compression/src/System.IO.Compression.csproj
+++ b/src/libraries/System.IO.Compression/src/System.IO.Compression.csproj
@@ -10,9 +10,8 @@
   <PropertyGroup Condition="'$(TargetOS)' != 'browser'
     and '$(TargetOS)' != 'wasi'
     and '$(RuntimeFlavor)' != 'Mono'">
-    <EnablePreviewFeatures>true</EnablePreviewFeatures>
+    <NoWarn>$(NoWarn);CA2252</NoWarn>
     <Features>$(Features);runtime-async=on</Features>
-    <NoWarn>$(NoWarn);SYSLIB5007</NoWarn>
   </PropertyGroup>
 
   <!-- DesignTimeBuild requires all the TargetFramework Derived Properties to not be present in the first property group. -->
diff --git a/src/libraries/System.Net.WebSockets/src/System.Net.WebSockets.csproj b/src/libraries/System.Net.WebSockets/src/System.Net.WebSockets.csproj
index 4b1229be09da56..3e5221752ee3ce 100644
--- a/src/libraries/System.Net.WebSockets/src/System.Net.WebSockets.csproj
+++ b/src/libraries/System.Net.WebSockets/src/System.Net.WebSockets.csproj
@@ -6,6 +6,13 @@
     <UseCompilerGeneratedDocXmlFile>false</UseCompilerGeneratedDocXmlFile>
   </PropertyGroup>
 
+  <PropertyGroup Condition="'$(TargetOS)' != 'browser'
+    and '$(TargetOS)' != 'wasi'
+    and '$(RuntimeFlavor)' != 'Mono'">
+    <NoWarn>$(NoWarn);CA2252</NoWarn>
+    <Features>$(Features);runtime-async=on</Features>
+  </PropertyGroup>
+
   <!-- DesignTimeBuild requires all the TargetFramework Derived Properties to not be present in the first property group. -->
   <PropertyGroup>
     <TargetPlatformIdentifier>$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)'))</TargetPlatformIdentifier>