Add Typeform to the list of supported providers

src/OpenIddict.Client.WebIntegration/OpenIddictClientWebIntegrationHandlers.cs

@@ -1276,13 +1276,17 @@ public static partial class OpenIddictClientWebIntegrationHandlers
                 // Trovo returns the username as a custom "userName" node:
                 ProviderTypes.Trovo => (string?) context.UserinfoResponse?["userName"],
 
+                // Typeform returns the username as a custom "alias" node:
+                ProviderTypes.Typeform => (string?) context.UserinfoResponse?["alias"],
+
                 _ => context.MergedPrincipal.GetClaim(ClaimTypes.Name)
             });
 
             context.MergedPrincipal.SetClaim(ClaimTypes.NameIdentifier, issuer: issuer, value: context.Registration.ProviderType switch
             {
                 // These providers return the user identifier as a custom "user_id" node:
-                ProviderTypes.Amazon or ProviderTypes.HubSpot or ProviderTypes.StackExchange
+                ProviderTypes.Amazon        or ProviderTypes.HubSpot or
+                ProviderTypes.StackExchange or ProviderTypes.Typeform
                     => (string?) context.UserinfoResponse?["user_id"],
 
                 // ArcGIS and Trakt don't return a user identifier and require using the username as the identifier:

src/OpenIddict.Client.WebIntegration/OpenIddictClientWebIntegrationProviders.xml

@@ -1964,6 +1964,32 @@
     </Setting>
   </Provider>
 
+  <!--
+                                      ▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄
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+                                      ███ ████▄▀▀▀▄██ ▀▀ ██ ▄▄▄██ ▄▄███ ███ ██ ▀▀▄██ █ █ ██
+                                      ███ ██████ ████ █████ ▀▀▀██ █████ ▀▀▀ ██ ██ ██ ███ ██
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+  -->
+
+  <Provider Name="Typeform" Id="7100d684-c02b-4da2-86bc-d6c42b117fee"
+            Documentation="https://www.typeform.com/developers/get-started/applications/">
+    <Environment Issuer="https://www.typeform.com/">
+      <Configuration AuthorizationEndpoint="https://api.typeform.com/oauth/authorize"
+                     TokenEndpoint="https://api.typeform.com/oauth/token"
+                     UserinfoEndpoint="https://api.typeform.com/me">
+        <GrantType Value="authorization_code" />
+        <GrantType Value="refresh_token" />
+      </Configuration>
+
+      <!--
+        Note: Typeform requires sending the "accounts:read" scope to be able to use the userinfo endpoint.
+      -->
+
+      <Scope Name="accounts:read" Default="true" Required="true" />
+    </Environment>
+  </Provider>
+
   <!--
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