Yes, I wait @Sherzod to analized situation. At this moment I try, but XMLHttpRequest dont show any message, and MainForm.onAjax dont fire.: procedure TUniMainModule.UniGUIMainModuleCreate(Sender: TObject);     function  getIPDetails (sRemIP: String): String;    var   sRemoteCountry      : String;   begin   TRY       UniSession.AddJS  ('  new Promise(function(resolve, reject) {' +                         ' const xhttp = new XMLHttpRequest();' //