add API spec: IsEnhancedSecurityModeEnabled

specs/IsEnhancedSecurityModeEnabled.md

@@ -0,0 +1,114 @@
+IsEnhancedSecurityModeEnabled API
+===
+
+# Background
+
+Enhanced Security Mode (ESM) is a Microsoft Edge security feature that reduces the risk of memory-related vulnerabilities by disabling JavaScript Just-in-Time (JIT) compilation and enabling additional operating system protections.
+
+In WebView2, ESM is off by default to avoid performance impact. Host applications can enable ESM for stricter security when rendering untrusted or sensitive content. While this improves security, it may reduce JavaScript performance.
+
+In Microsoft Edge, ESM offers two states:
+
+- Balanced – Enabled only for unfamiliar sites based on browsing heuristics.
+- Strict – Always enabled for all sites.
+
+![image](https://github.com/MicrosoftEdge/WebView2Feedback/assets/82386753/35977716-e46c-4257-82da-906b0c6f833e)
+
+Unlike Edge browser, WebView2 does not support heuristic-based “Balanced” state. The Only options are available: Off or Strict.
+
+Currently, ESM can only be configured via the --sdsm-state browser flag([see for more details](https://learn.microsoft.com/en-us/microsoft-edge/webview2/concepts/webview-features-flags?tabs=dotnetcsharp)) at environment creation, applying globally to all profiles.
+This proposal introduces a profile-level API to enable or disable ESM and persist the setting in the user data folder, giving developers fine-grained control without relying on global flags..
+
+## CoreWebView2Profile.IsEnhancedSecurityModeEnabled
+Enables or disables Enhanced Security Mode (ESM) for all WebView2 instances sharing the same profile. The setting is persisted in the user data folder. Default is false.
+
+- true: ESM enabled in Strict state: disables JavaScript JIT and applies additional OS protections.
+- false: ESM state is Off.
+
+Changes apply to future navigations; reload may be required. Enabling ESM improves security but can reduce JavaScript performance.
+
+# Examples
+
+## IsEnhancedSecurityModeEnabled
+
+Enable Enhanced Security Mode for a profile.
+
+```c#
+void EnableEnhancedSecurityMode()
+{
+    var profile = webView2.CoreWebView2.Profile;
+    profile.IsEnhancedSecurityModeEnabled = true;
+    MessageBox.Show(this, "Enhanced security mode is enabled", "Enhanced Security Mode");
+}
+```
+
+```cpp
+void EnableEnhancedSecurityMode()
+{
+    wil::com_ptr<ICoreWebView2_13> webView2_13;
+    webView2_13 = m_webView.try_query<ICoreWebView2_13>();
+
+    if (webView2_13)
+    {
+        wil::com_ptr<ICoreWebView2Profile> profile;
+        CHECK_FAILURE(webView2_13->get_Profile(&profile));
+
+        auto profile12 = profile.try_query<ICoreWebView2Profile12>();
+        if (profile12)
+        {
+            CHECK_FAILURE(profile12->put_IsEnhancedSecurityModeEnabled(TRUE));
+            MessageBox(
+                nullptr, L"Enhanced security mode is enabled",
+                L"Enhanced Security Mode", MB_OK);
+        }
+    }
+}
+```
+
+# API Details
+
+```c#
+/// Extension of ICoreWebView2Profile to control Enhanced Security Mode (ESM).
+///
+/// ESM reduces the risk of memory-related vulnerabilities by disabling JavaScript
+/// Just-in-Time (JIT) compilation and enabling additional OS protections.
+/// This property applies to all WebView2 instances sharing the same profile and
+/// is persisted in the user data folder.
+///
+/// Default: false. ESM state is Off.
+///
+/// true: Enables ESM in Strict state for all sites.
+/// false: ESM state is Off.
+///
+/// Notes:
+/// - Changes apply to future navigations; reload may be required.
+/// - Enabling ESM improves security but may reduce JavaScript performance.
+///
+/// See: https://learn.microsoft.com/en-us/DeployEdge/microsoft-edge-security-browse-safer
+///
+///
+[uuid(d5b781db-0a75-5f9c-85b1-40fa814fcea7), object, pointer_default(unique)]
+interface ICoreWebView2Profile12 : IUnknown {
+  /// Gets whether Enhanced Security Mode is enabled for this profile.
+  [propget] HRESULT IsEnhancedSecurityModeEnabled([out, retval] BOOL* value);
+
+  /// Enables or disables Enhanced Security Mode for this profile.
+  /// See notes above for behavior and performance impact.
+  [propput] HRESULT IsEnhancedSecurityModeEnabled([in] BOOL value);
+}
+```
+
+```c# 
+namespace Microsoft.Web.WebView2.Core
+{
+    runtimeclass CoreWebView2Profile
+    {
+        // ...
+        [interface_name("Microsoft.Web.WebView2.Core.ICoreWebView2Profile12")]
+        {
+            // ICoreWebView2Profile12 members
+            Boolean IsEnhancedSecurityModeEnabled { get; set; };
+        }
+    }
+}
+```