Encode the `returnUrl` if it start with `/connect/authorize?`.

modules/account/src/Volo.Abp.Account.Application/Volo/Abp/Account/Emailing/AccountEmailer.cs

@@ -101,6 +101,11 @@ public class AccountEmailer : IAccountEmailer, ITransientDependency
             }
         }
 
+        if (returnUrl.StartsWith("/connect/authorize?", StringComparison.OrdinalIgnoreCase))
+        {
+            return HttpUtility.UrlEncode(returnUrl);
+        }
+
         return returnUrl;
     }
 }