# System.Security.Cryptography

``` diff
 namespace System.Security.Cryptography {
-    [UnsupportedOSPlatformAttribute("browser")]
-    public class HMACSHA1 : HMAC
+    public class HMACSHA1 : HMAC
-    [UnsupportedOSPlatformAttribute("browser")]
-    public class HMACSHA256 : HMAC
+    public class HMACSHA256 : HMAC
-    [UnsupportedOSPlatformAttribute("browser")]
-    public class HMACSHA384 : HMAC
+    public class HMACSHA384 : HMAC
-    [UnsupportedOSPlatformAttribute("browser")]
-    public class HMACSHA512 : HMAC
+    public class HMACSHA512 : HMAC
     public sealed class IncrementalHash : IDisposable {
-        [UnsupportedOSPlatformAttribute("browser")]
-        public static IncrementalHash CreateHMAC(HashAlgorithmName hashAlgorithm, byte[] key);
+        public static IncrementalHash CreateHMAC(HashAlgorithmName hashAlgorithm, byte[] key);
-        [UnsupportedOSPlatformAttribute("browser")]
-        public static IncrementalHash CreateHMAC(HashAlgorithmName hashAlgorithm, ReadOnlySpan<byte> key);
+        public static IncrementalHash CreateHMAC(HashAlgorithmName hashAlgorithm, ReadOnlySpan<byte> key);
     }
     public static class PemEncoding {
+        public static string WriteString(ReadOnlySpan<char> label, ReadOnlySpan<byte> data);
     }
 }
```

