Add Box to the list of supported providers

src/OpenIddict.Client.WebIntegration/OpenIddictClientWebIntegrationHandlers.cs

@@ -1242,13 +1242,13 @@ public static partial class OpenIddictClientWebIntegrationHandlers
                     => (string?) context.UserinfoResponse?["username"],
 
                 // These providers return the user identifier as a custom "id" node:
-                ProviderTypes.Basecamp   or ProviderTypes.Dailymotion or ProviderTypes.Deezer        or
-                ProviderTypes.Discord    or ProviderTypes.Disqus      or ProviderTypes.Facebook      or
-                ProviderTypes.GitHub     or ProviderTypes.Harvest     or ProviderTypes.Kroger        or
-                ProviderTypes.Lichess    or ProviderTypes.Mastodon    or ProviderTypes.Meetup        or
-                ProviderTypes.Nextcloud  or ProviderTypes.Patreon     or ProviderTypes.Reddit        or
-                ProviderTypes.Smartsheet or ProviderTypes.Spotify     or ProviderTypes.SubscribeStar or
-                ProviderTypes.Twitter    or ProviderTypes.Zoom
+                ProviderTypes.Basecamp      or ProviderTypes.Box        or ProviderTypes.Dailymotion or
+                ProviderTypes.Deezer        or ProviderTypes.Discord    or ProviderTypes.Disqus      or
+                ProviderTypes.Facebook      or ProviderTypes.GitHub     or ProviderTypes.Harvest     or
+                ProviderTypes.Kroger        or ProviderTypes.Lichess    or ProviderTypes.Mastodon    or
+                ProviderTypes.Meetup        or ProviderTypes.Nextcloud  or ProviderTypes.Patreon     or
+                ProviderTypes.Reddit        or ProviderTypes.Smartsheet or ProviderTypes.Spotify     or
+                ProviderTypes.SubscribeStar or ProviderTypes.Twitter    or ProviderTypes.Zoom
                     => (string?) context.UserinfoResponse?["id"],
 
                 // Bitbucket returns the user identifier as a custom "uuid" node:

src/OpenIddict.Client.WebIntegration/OpenIddictClientWebIntegrationProviders.xml

@@ -264,6 +264,26 @@
     </Environment>
   </Provider>
 
+  <!--
+                                                      ▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄
+                                                      ██ ▄▄▀██ ▄▄▄ █▄▀█▀▄██
+                                                      ██ ▄▄▀██ ███ ███ ████
+                                                      ██ ▀▀ ██ ▀▀▀ █▀▄█▄▀██
+                                                      ▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀
+  -->
+
+  <Provider Name="Box" Id="09100499-f6a9-4f71-b561-2dc9f18d751f"
+            Documentation="https://developer.box.com/guides/authentication/oauth2/oauth2-setup/">
+    <Environment Issuer="https://account.box.com/">
+      <Configuration AuthorizationEndpoint="https://account.box.com/api/oauth2/authorize"
+                     TokenEndpoint="https://api.box.com/oauth2/token"
+                     UserinfoEndpoint="https://api.box.com/2.0/users/me">
+        <GrantType Value="authorization_code" />
+        <GrantType Value="refresh_token" />
+      </Configuration>
+    </Environment>
+  </Provider>
+
   <!--
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