https://learn.microsoft.com/en-us/dotnet/api/system.web.mvc.ajaxrequestextensions.isajaxrequest?view=aspnet-mvc-5.2&redirectedfrom=MSDN
AjaxRequestExtensions.IsAjaxRequest(HttpRequestBase) Method (System.Web.Mvc) | Microsoft Learn
Determines whether the specified HTTP request is an AJAX request.
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