Fix the invalid metadata returned by the discovery endpoint

src/OpenIddict/OpenIddictProvider.Discovery.cs

@@ -41,7 +41,7 @@ namespace OpenIddict
 
             // Note: the optional "claims" parameter is not supported by OpenIddict,
             // so a "false" flag is returned to encourage clients not to use it.
-            context.Metadata[OpenIdConnectConstants.Metadata.ClaimsSupported] = false;
+            context.Metadata[OpenIdConnectConstants.Metadata.ClaimsParameterSupported] = false;
 
             var schemes = context.HttpContext.RequestServices.GetRequiredService<IAuthenticationSchemeProvider>();
 

test/OpenIddict.Tests/OpenIddictProviderTests.Discovery.cs

@@ -138,6 +138,21 @@ namespace OpenIddict.Tests
                 ((JArray) response[OpenIdConnectConstants.Metadata.ScopesSupported]).Values<string>());
         }
 
+        [Fact]
+        public async Task HandleConfigurationRequest_ClaimsParameterSupportedIsReturned()
+        {
+            // Arrange
+            var server = CreateAuthorizationServer();
+
+            var client = new OpenIdConnectClient(server.CreateClient());
+
+            // Act
+            var response = await client.GetAsync(ConfigurationEndpoint);
+
+            // Assert
+            Assert.False((bool) response[OpenIdConnectConstants.Metadata.ClaimsParameterSupported]);
+        }
+
         [Fact]
         public async Task HandleConfigurationRequest_ExternalProvidersAreCorrectlyReturned()
         {