diff --git a/src/AutoConnect.cpp b/src/AutoConnect.cpp
index 570a017..1caaba7 100644
--- a/src/AutoConnect.cpp
+++ b/src/AutoConnect.cpp
@@ -393,6 +393,7 @@ void AutoConnect::_startWebServer() {
   if (!_responsePage) {
     _responsePage = new PageBuilder();
     _responsePage->chunked(AUTOCONNECT_HTTP_TRANSFER);
+    _responsePage->reserve(AUTOCONNECT_CONTENTBUFFER_SIZE);
     _responsePage->exitCanHandle(std::bind(&AutoConnect::_classifyHandle, this, std::placeholders::_1, std::placeholders::_2));
     _responsePage->insert(*_webServer);
 
@@ -460,7 +461,7 @@ void AutoConnect::handleRequest() {
           AC_DBG("%s credential saved\n", reinterpret_cast<const char*>(_credential.ssid));
         }
 
-        // Ensures that keeps a connection with the current AP while the portal behaves. 
+        // Ensures that keeps a connection with the current AP while the portal behaves.
         _setReconnect(AC_RECONNECT_SET);
       }
       else
@@ -600,8 +601,8 @@ bool AutoConnect::_captivePortal() {
   String  hostHeader = _webServer->hostHeader();
   if (!_isIP(hostHeader) && (hostHeader != WiFi.localIP().toString())) {
     String location = String(F("http://")) + _webServer->client().localIP().toString() + String(AUTOCONNECT_URI);
-    _webServer->sendHeader(F("Location"), location, true);
-    _webServer->send(302, F("text/plain"), "");
+    _webServer->sendHeader(String(F("Location")), location, true);
+    _webServer->send(302, String(F("text/plain")), "");
     _webServer->client().flush();
     _webServer->client().stop();
     return true;
@@ -649,13 +650,13 @@ void AutoConnect::_handleNotFound() {
       _notFoundHandler();
     }
     else {
-      PageElement page404(_PAGE_404, { { "HEAD", std::bind(&AutoConnect::_token_HEAD, this, std::placeholders::_1) } });
+      PageElement page404(_PAGE_404, { { String(F("HEAD")), std::bind(&AutoConnect::_token_HEAD, this, std::placeholders::_1) } });
       String html = page404.build();
-      _webServer->sendHeader(F("Cache-Control"), F("no-cache, no-store, must-revalidate"), true);
-      _webServer->sendHeader(F("Pragma"), F("no-cache"));
-      _webServer->sendHeader(F("Expires"), F("-1"));
-      _webServer->sendHeader(F("Content-Length"), String(html.length()));
-      _webServer->send(404, F("text/html"), html);
+      _webServer->sendHeader(String(F("Cache-Control")), String(F("no-cache, no-store, must-revalidate")), true);
+      _webServer->sendHeader(String(F("Pragma")), String(F("no-cache")));
+      _webServer->sendHeader(String(F("Expires")), String("-1"));
+      _webServer->sendHeader(String(F("Content-Length")), String(html.length()));
+      _webServer->send(404, String(F("text/html")), html);
     }
   }
 }
@@ -709,7 +710,7 @@ String AutoConnect::_induceConnect(PageArgument& args) {
   _rfConnect = true;
 
 // Since v0.9.7, the redirect method changed from a 302 response to the
-// meta tag with refresh attribute.  
+// meta tag with refresh attribute.
 // This approach for ESP32 makes an inefficient choice. The waiting
 // procedure for a connection attempt should be the server side. Also,
 // the proper value of waiting time until refreshing is unknown. But
@@ -730,9 +731,8 @@ String AutoConnect::_induceConnect(PageArgument& args) {
   // String url = String(F("http://")) + _webServer->client().localIP().toString() + String(AUTOCONNECT_URI_RESULT);
   // _webServer->sendHeader(F("Location"), url, true);
   // _webServer->send(302, F("text/plain"), "");
-  // _webServer->client().stop();
   // _webServer->client().flush();
-  // _waitForEndTransmission();  // Wait for response transmission complete
+  // _webServer->client().stop();
   // _responsePage->cancel();
   return String("");
 }
@@ -742,10 +742,11 @@ String AutoConnect::_induceConnect(PageArgument& args) {
  *  A destination as _redirectURI is indicated by loop to establish connection.
  */
 String AutoConnect::_invokeResult(PageArgument& args) {
+  AC_DBG("_invokeResult entered\n");
   String redirect = String(F("http://"));
   // The host address to which the connection result for ESP32 responds
   // changed from v0.9.7. This change is a measure according to the
-  // implementation of the arduino-esp32 1.0.1 core.
+  // implementation of the arduino-esp32 1.0.1.
 #if defined(ARDUINO_ARCH_ESP32)
   // In ESP32, the station IP address just established could not be reached.
   redirect += _webServer->client().localIP().toString();
@@ -756,10 +757,10 @@ String AutoConnect::_invokeResult(PageArgument& args) {
   redirect += _currentHostIP.toString();
 #endif
   redirect += _redirectURI;
-  _webServer->sendHeader(F("Location"), redirect, true);
-  _webServer->send(302, F("text/plain"), "");
-  _webServer->client().stop();
+  _webServer->sendHeader(String(F("Location")), redirect, true);
+  _webServer->send(302, String(F("text/plain")), "");
   _webServer->client().flush();
+  _webServer->client().stop();
   _waitForEndTransmission();  // Wait for response transmission complete
   _responsePage->cancel();
   return String("");
diff --git a/src/AutoConnectElementBasisImpl.h b/src/AutoConnectElementBasisImpl.h
index 01d3af1..ec64f67 100644
--- a/src/AutoConnectElementBasisImpl.h
+++ b/src/AutoConnectElementBasisImpl.h
@@ -18,7 +18,7 @@
  * @return  An HTML string.
  */
 const String AutoConnectButtonBasis::toHTML(void) const {
-  return String(FPSTR("<button type=\"button\" name=\"")) + name + String(FPSTR("\" value=\"")) + value + String(FPSTR("\" onclick=\"")) + action + String("\">") + value + String(FPSTR("</button>"));
+  return String(F("<button type=\"button\" name=\"")) + name + String(F("\" value=\"")) + value + String(F("\" onclick=\"")) + action + String("\">") + value + String(F("</button>"));
 }
 
 /**
@@ -32,34 +32,34 @@ const String AutoConnectButtonBasis::toHTML(void) const {
 const String AutoConnectCheckboxBasis::toHTML(void) const {
   String  html;
 
-  html = String(FPSTR("<input type=\"checkbox\" name=\"")) + name + String(FPSTR("\" value=\"")) + value + String("\"");
+  html = String(F("<input type=\"checkbox\" name=\"")) + name + String(F("\" value=\"")) + value + String("\"");
   if (checked)
-    html += String(FPSTR(" checked"));
+    html += String(F(" checked"));
   if (label.length())
-    html += String(" id=\"") + name + String("\"><label for=\"") + name + String("\">") + label + String(FPSTR("</label"));
-  html += String(FPSTR("><br>"));
+    html += String(F(" id=\"")) + name + String(F("\"><label for=\"")) + name + String("\">") + label + String(F("</label"));
+  html += String(F("><br>"));
   return html;
 }
 
 /**
- *  Generate an HTML <input type=text> element.
- *  If the value member is contained, it is reflected in the placeholder
- *  attribute. The entered value can be obtained using the user callback
- *  function registered by AutoConnectAux::on after the form is sent in
- *  combination with AutoConnectSubmit.
- *  @return String  an HTML string.
+ * Generate an HTML <input type=text> element.
+ * If the value member is contained, it is reflected in the placeholder
+ * attribute. The entered value can be obtained using the user callback
+ * function registered by AutoConnectAux::on after the form is sent in
+ * combination with AutoConnectSubmit.
+ * @return String  an HTML string.
  */
 const String AutoConnectInputBasis::toHTML(void) const {
-  String  html = String();
+  String  html = String("");
 
   if (label.length())
-    html = String(FPSTR("<label for=\"")) + name + String("\">") + label + String(FPSTR("</label>"));
-  html += String(FPSTR("<input type=\"text\" id=\"")) + name + String(FPSTR("\" name=\"")) + name + String("\"");
+    html = String(F("<label for=\"")) + name + String("\">") + label + String(F("</label>"));
+  html += String(F("<input type=\"text\" id=\"")) + name + String(F("\" name=\"")) + name + String("\"");
   if (placeholder.length())
-    html += String(FPSTR(" placeholder=\"")) + placeholder + String("\"");
+    html += String(F(" placeholder=\"")) + placeholder + String("\"");
   if (value.length())
-    html += String(FPSTR(" value=\"")) + value + String("\"");
-  html += String(FPSTR("><br>"));
+    html += String(F(" value=\"")) + value + String("\"");
+  html += String(F("><br>"));
 
   return html;
 }
@@ -91,31 +91,39 @@ void AutoConnectRadioBasis::empty(const size_t reserve) {
 }
 
 /**
- *  Generate an HTML <input type=radio> element with an <option> element.
- *  @return String  an HTML string.
+ * Generate an HTML <input type=radio> element with an <option> element.
+ * @return String  an HTML string.
  */
 const String AutoConnectRadioBasis::toHTML(void) const {
-  String  html = "";
+  String  html = String("");
 
   if (label.length()) {
     html = label;
     if (order == AC_Vertical)
-      html += String("<br>");
+      html += String(F("<br>"));
   }
   uint8_t n = 0;
   for (const String value : _values) {
     n++;
     String  id = name + "_" + String(n);
-    html += String(FPSTR("<input type=\"radio\" name=\"")) + name + String(FPSTR("\" id=\"")) + id + String(FPSTR("\" value=\"")) + value + String("\"");
+    html += String(F("<input type=\"radio\" name=\"")) + name + String(F("\" id=\"")) + id + String(F("\" value=\"")) + value + String("\"");
     if (n == checked - 1)
-      html += String(FPSTR(" checked"));
-    html += String(FPSTR("><label for=\"")) + id + String("\">") + value + String(FPSTR("</label>"));
+      html += String(F(" checked"));
+    html += String(F("><label for=\"")) + id + String("\">") + value + String(F("</label>"));
     if (order == AC_Vertical)
-      html += String("<br>");
+      html += String(F("<br>"));
   }
   return html;
 }
 
+/**
+ * Returns current selected value in the radio same group
+ */
+const String& AutoConnectRadioBasis::value() const {
+  static const String _nullString = String();
+  return checked ? _values.at(checked - 1) : _nullString;
+}
+
 /**
  * Clear option items of AutoConnectSelect and reallocate new storage.
  * All hold items are released.
@@ -130,42 +138,42 @@ void AutoConnectSelectBasis::empty(const size_t reserve) {
 }
 
 /**
- *  Generate an HTML <select> element with an <option> element.
- *  The attribute value of the <option> element is given to the
- *  AutoConnectSelect class as a string array, which would be stored
- *  in the 'options' member. If a label member is contained, the <label>
- *  element would be generated the preface of <select>.
- *  @return String  an HTML string.
+ * Generate an HTML <select> element with an <option> element.
+ * The attribute value of the <option> element is given to the
+ * AutoConnectSelect class as a string array, which would be stored
+ * in the 'options' member. If a label member is contained, the <label>
+ * element would be generated the preface of <select>.
+ * @return String  an HTML string.
  */
 const String AutoConnectSelectBasis::toHTML(void) const {
-  String  html = "";
+  String  html = String("");
 
   if (label.length())
-    html = String(FPSTR("<label for=\"")) + name + String("\">") + label + String(FPSTR("</label>"));
-  html += String(FPSTR("<select name=\"")) + name + String("\" id=\"") + name + String("\">");
+    html = String(F("<label for=\"")) + name + String("\">") + label + String(F("</label>"));
+  html += String(F("<select name=\"")) + name + String(F("\" id=\"")) + name + String("\">");
   for (const String option : _options)
-    html += String(FPSTR("<option value=\"")) + option + "\">" + option + String(FPSTR("</option>"));
-  html += String(FPSTR("</select>"));
+    html += String(F("<option value=\"")) + option + "\">" + option + String(F("</option>"));
+  html += String(F("</select>"));
   return html;
 }
 
 /**
- *  Generate an HTML <input type=button> element. This element is used
- *  for form submission. An 'onclick' attribute calls fixed JavaScript
- *  code as 'sa' named and it's included in the template.
- *  @return String  an HTML string.
+ * Generate an HTML <input type=button> element. This element is used
+ * for form submission. An 'onclick' attribute calls fixed JavaScript
+ * code as 'sa' named and it's included in the template.
+ * @return String  an HTML string.
  */
 const String AutoConnectSubmitBasis::toHTML(void) const {
-  return String(FPSTR("<input type=\"button\" name=\"")) + name + String(FPSTR("\" value=\"")) + value + String(FPSTR("\" onclick=\"_sa('")) + uri + String("')\">");
+  return String(F("<input type=\"button\" name=\"")) + name + String(F("\" value=\"")) + value + String(F("\" onclick=\"_sa('")) + uri + String("')\">");
 }
 
 /**
- *  Generate an HTML text element from a string of the value member. If a style
- *  exists, it gives a style attribute.
- *  @return String  an HTML string.
+ * Generate an HTML text element from a string of the value member. If a style
+ * exists, it gives a style attribute.
+ * @return String  an HTML string.
  */
 const String AutoConnectTextBasis::toHTML(void) const {
-  return String(FPSTR("<div style=\"")) + style + String("\">") + value + String(FPSTR("</div>"));
+  return String(F("<div style=\"")) + style + String("\">") + value + String(F("</div>"));
 }
 
 #endif // _AUTOCONNECTELEMENTBASISIMPL_H_
diff --git a/src/AutoConnectPage.cpp b/src/AutoConnectPage.cpp
index 01b509c..c76648f 100644
--- a/src/AutoConnectPage.cpp
+++ b/src/AutoConnectPage.cpp
@@ -711,7 +711,7 @@ const char  AutoConnect::_PAGE_OPENCREDT[] PROGMEM = {
 const char  AutoConnect::_PAGE_CONNECTING[] PROGMEM = {
   "{{REQ}}"
   "{{HEAD}}"
-    "<meta http-equiv=\"refresh\" content=\"0;url=" AUTOCONNECT_URI_RESULT "\">"
+    "<meta http-equiv=\"refresh\" content=\"1;url=" AUTOCONNECT_URI_RESULT "\">"
     "<title>AutoConnect connecting</title>"
     "<style type=\"text/css\">"
       "{{CSS_BASE}}"
@@ -729,13 +729,13 @@ const char  AutoConnect::_PAGE_CONNECTING[] PROGMEM = {
       "{{MENU_PRE}}"
       "{{MENU_POST}}"
       "<div class=\"spinner\">"
-        "<div style=\"position:absolute;left:-100%;right:-100%;text-align:center;margin:10px auto;font-weight:bold;color:#4169e1;\">{{CUR_SSID}}</div>"
         "<div class=\"double-bounce1\"></div>"
         "<div class=\"double-bounce2\"></div>"
+        "<div style=\"position:absolute;left:-100%;right:-100%;text-align:center;margin:10px auto;font-weight:bold;color:#4169e1;\">{{CUR_SSID}}</div>"
       "</div>"
     "</div>"
   "</body>"
-  "</html>" 
+  "</html>"
 };
 
 /**< A page announcing that a connection has been established. */
@@ -1025,7 +1025,7 @@ String AutoConnect::_token_STATION_STATUS(PageArgument& args) {
     wlStatusSymbol = wlStatusSymbols[7];
 #endif
   }
-  return "(" + String(_rsConnect) + ") " + String(wlStatusSymbol);
+  return String("(") + String(_rsConnect) + String(") ") + String(wlStatusSymbol);
 }
 
 String AutoConnect::_token_LOCAL_IP(PageArgument& args) {
@@ -1090,7 +1090,7 @@ String AutoConnect::_token_CHIP_ID(PageArgument& args) {
 
 String AutoConnect::_token_FREE_HEAP(PageArgument& args) {
   AC_UNUSED(args);
-  return String(ESP.getFreeHeap());
+  return String(_freeHeapSize);
 }
 
 String AutoConnect::_token_LIST_SSID(PageArgument& args) {
@@ -1103,7 +1103,7 @@ String AutoConnect::_token_LIST_SSID(PageArgument& args) {
   for (uint8_t i = 0; i < nn; i++) {
     String ssid = WiFi.SSID(i);
     if (ssid.length() > 0) {
-      ssidList += String(F("<input type=\"button\" onClick=\"document.getElementById('ssid').value=this.getAttribute('value');document.getElementById('passphrase').focus()\" value=\"")) + ssid + String(F("\">"));
+      ssidList += String(F("<input type=\"button\" onClick=\"document.getElementById('ssid').value=this.getAttribute('value');document.getElementById('passphrase').focus()\" value=\"")) + ssid + String("\">");
       ssidList += String(F("<label>")) + String(AutoConnect::_toWiFiQuality(WiFi.RSSI(i))) + String(F("&#037;</label>"));
       if (WiFi.encryptionType(i) != ENC_TYPE_NONE)
         ssidList += String(F("<span class=\"img-lock\"></span>"));
@@ -1192,6 +1192,7 @@ PageElement* AutoConnect::_setupPage(String uri) {
   if (uri == String(AUTOCONNECT_URI)) {
 
     // Setup /auto
+    _freeHeapSize = ESP.getFreeHeap();
     elm->setMold(_PAGE_STAT);
     elm->addToken(String(FPSTR("HEAD")), std::bind(&AutoConnect::_token_HEAD, this, std::placeholders::_1));
     elm->addToken(String(FPSTR("CSS_BASE")), std::bind(&AutoConnect::_token_CSS_BASE, this, std::placeholders::_1));