mfa class:

- automatic submit to jump to MFA server
- generate automatic back url to current page

src/mfaclient.class.php

@@ -234,7 +234,7 @@ class mfaclient
                 ? ''
                 : "<script>
                     window.onload = function() {
-                        // document.getElementById('$sFormId').submit();
+                        document.getElementById('$sFormId').submit();
                     }
                 </script>"
             )
@@ -428,8 +428,8 @@ class mfaclient
     /**
      * Get an html button to open mfa setup page
      * 
-     * @param string $sSubmitBtn  html code for a submit button
-     * @param string $sBackUrl    url to return from mfa server to the application
+     * @param string $sSubmitBtn  optional: html code for a submit button; default: '<button>MFA Setup</button>'
+     * @param string $sBackUrl    optional: url to return from mfa server to the application; default: current url
      * @return void
      */
     public function getButtonSetup(string $sSubmitBtn = '<button>MFA Setup</button>', $sBackUrl = ''): string
@@ -438,7 +438,7 @@ class mfaclient
         // print_r($aBody);
         $sUrl = $aBody['setup'] ?? '';
         if ($sUrl) {
-            $sBackUrl = $sBackUrl ?: $_SERVER['HTTP_REFERER'];
+            $sBackUrl = $sBackUrl ?: ( "http".(($_SERVER['HTTPS']??'') === 'on' ? "s" : "")."://$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]");
             return $this->jumpform($sUrl, $sSubmitBtn, $sBackUrl);
         } else {
             return $aBody['message']??'';