diff --git a/.gitignore b/.gitignore
index 49359a587..f9c30939b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,3 +4,5 @@
 .gcc-flags.json
 .vscode
 sonoff/user_config_override.h
+.vscode/c_cpp_properties.json
+.vscode/launch.json
diff --git a/README.md b/README.md
index 55db531b1..07372cdd6 100644
--- a/README.md
+++ b/README.md
@@ -1,7 +1,7 @@
 ## Sonoff-Tasmota
 Provide ESP8266 based Sonoff by [iTead Studio](https://www.itead.cc/) and ElectroDragon IoT Relay with Serial, Web and MQTT control allowing 'Over the Air' or OTA firmware updates using Arduino IDE.
 
-Current version is **5.12.0b** - See [sonoff/_releasenotes.ino](https://github.com/arendst/Sonoff-Tasmota/blob/development/sonoff/_releasenotes.ino) for change information.
+Current version is **5.12.0c** - See [sonoff/_releasenotes.ino](https://github.com/arendst/Sonoff-Tasmota/blob/development/sonoff/_releasenotes.ino) for change information.
 
 ### ATTENTION All versions
 
diff --git a/lib/readme.txt b/lib/readme.txt
new file mode 100644
index 000000000..dbadc3d63
--- /dev/null
+++ b/lib/readme.txt
@@ -0,0 +1,36 @@
+
+This directory is intended for the project specific (private) libraries.
+PlatformIO will compile them to static libraries and link to executable file.
+
+The source code of each library should be placed in separate directory, like
+"lib/private_lib/[here are source files]".
+
+For example, see how can be organized `Foo` and `Bar` libraries:
+
+|--lib
+|  |--Bar
+|  |  |--docs
+|  |  |--examples
+|  |  |--src
+|  |     |- Bar.c
+|  |     |- Bar.h
+|  |--Foo
+|  |  |- Foo.c
+|  |  |- Foo.h
+|  |- readme.txt --> THIS FILE
+|- platformio.ini
+|--src
+   |- main.c
+
+Then in `src/main.c` you should use:
+
+#include <Foo.h>
+#include <Bar.h>
+
+// rest H/C/CPP code
+
+PlatformIO will find your libraries automatically, configure preprocessor's
+include paths and build them.
+
+More information about PlatformIO Library Dependency Finder
+- http://docs.platformio.org/page/librarymanager/ldf.html
diff --git a/sonoff/_releasenotes.ino b/sonoff/_releasenotes.ino
index c228c4e6d..c8a55101a 100644
--- a/sonoff/_releasenotes.ino
+++ b/sonoff/_releasenotes.ino
@@ -1,5 +1,7 @@
 /* 5.12.0c
  * Fix intermittent exception when dns lookup is used while sleep is enabled
+ * Fix 5.4.0 regression turning off single press after button hold during 4x hold time
+ * Fix possible wifi connection problem by erasing sdk configuration parameters
  *
  * 5.12.0b
  * Add serial debug info
diff --git a/sonoff/settings.ino b/sonoff/settings.ino
index f77955ebd..c702d16c2 100644
--- a/sonoff/settings.ino
+++ b/sonoff/settings.ino
@@ -185,14 +185,11 @@ void SetFlashModeDout()
   eboot_command_read(&ebcmd);
   address = ebcmd.args[0];
   _buffer = new uint8_t[FLASH_SECTOR_SIZE];
-  if (SPI_FLASH_RESULT_OK == spi_flash_read(address, (uint32_t*)_buffer, FLASH_SECTOR_SIZE)) {
+
+  if (ESP.flashRead(address, (uint32_t*)_buffer, FLASH_SECTOR_SIZE)) {
     if (_buffer[2] != 3) {  // DOUT
       _buffer[2] = 3;
-      noInterrupts();
-      if (SPI_FLASH_RESULT_OK == spi_flash_erase_sector(address / FLASH_SECTOR_SIZE)) {
-        spi_flash_write(address, (uint32_t*)_buffer, FLASH_SECTOR_SIZE);
-      }
-      interrupts();
+      if (ESP.flashEraseSector(address / FLASH_SECTOR_SIZE)) ESP.flashWrite(address, (uint32_t*)_buffer, FLASH_SECTOR_SIZE);
     }
   }
   delete[] _buffer;
@@ -256,15 +253,11 @@ void SettingsSave(byte rotate)
       }
     }
     Settings.save_flag++;
-    noInterrupts();
-    spi_flash_erase_sector(settings_location);
-    spi_flash_write(settings_location * SPI_FLASH_SEC_SIZE, (uint32*)&Settings, sizeof(SYSCFG));
-    interrupts();
+    ESP.flashEraseSector(settings_location);
+    ESP.flashWrite(settings_location * SPI_FLASH_SEC_SIZE, (uint32*)&Settings, sizeof(SYSCFG));
     if (!stop_flash_rotate && rotate) {
       for (byte i = 1; i < CFG_ROTATES; i++) {
-        noInterrupts();
-        spi_flash_erase_sector(settings_location -i);  // Delete previous configurations by resetting to 0xFF
-        interrupts();
+        ESP.flashEraseSector(settings_location -i);  // Delete previous configurations by resetting to 0xFF
         delay(1);
       }
     }
@@ -289,10 +282,8 @@ void SettingsLoad()
   settings_location = SETTINGS_LOCATION +1;
   for (byte i = 0; i < CFG_ROTATES; i++) {
     settings_location--;
-    noInterrupts();
-    spi_flash_read(settings_location * SPI_FLASH_SEC_SIZE, (uint32*)&Settings, sizeof(SYSCFG));
-    spi_flash_read((settings_location -1) * SPI_FLASH_SEC_SIZE, (uint32*)&_SettingsH, sizeof(SYSCFGH));
-    interrupts();
+    ESP.flashRead(settings_location * SPI_FLASH_SEC_SIZE, (uint32*)&Settings, sizeof(SYSCFG));
+    ESP.flashRead((settings_location -1) * SPI_FLASH_SEC_SIZE, (uint32*)&_SettingsH, sizeof(SYSCFGH));
 
 //  snprintf_P(log_data, sizeof(log_data), PSTR("Cnfg: Check at %X with count %d and holder %X"), settings_location -1, _SettingsH.save_flag, _SettingsH.cfg_holder);
 //  AddLog(LOG_LEVEL_DEBUG);
@@ -307,15 +298,10 @@ void SettingsLoad()
   AddLog(LOG_LEVEL_DEBUG);
   if (Settings.cfg_holder != CFG_HOLDER) {
     // Auto upgrade
-    noInterrupts();
-    spi_flash_read((SETTINGS_LOCATION_3) * SPI_FLASH_SEC_SIZE, (uint32*)&Settings, sizeof(SYSCFG));
-    spi_flash_read((SETTINGS_LOCATION_3 + 1) * SPI_FLASH_SEC_SIZE, (uint32*)&_SettingsH, sizeof(SYSCFGH));
-    if (Settings.save_flag < _SettingsH.save_flag)
-      spi_flash_read((SETTINGS_LOCATION_3 + 1) * SPI_FLASH_SEC_SIZE, (uint32*)&Settings, sizeof(SYSCFG));
-    interrupts();
-    if ((Settings.cfg_holder != CFG_HOLDER) || (Settings.version >= 0x04020000)) {
-      SettingsDefault();
-    }
+    ESP.flashRead((SETTINGS_LOCATION_3) * SPI_FLASH_SEC_SIZE, (uint32*)&Settings, sizeof(SYSCFG));
+    ESP.flashRead((SETTINGS_LOCATION_3 + 1) * SPI_FLASH_SEC_SIZE, (uint32*)&_SettingsH, sizeof(SYSCFGH));
+    if (Settings.save_flag < _SettingsH.save_flag) ESP.flashRead((SETTINGS_LOCATION_3 + 1) * SPI_FLASH_SEC_SIZE, (uint32*)&Settings, sizeof(SYSCFG));
+    if ((Settings.cfg_holder != CFG_HOLDER) || (Settings.version >= 0x04020000)) SettingsDefault();
   }
 
   settings_hash = GetSettingsHash();
@@ -323,25 +309,33 @@ void SettingsLoad()
   RtcSettingsLoad();
 }
 
-void SettingsErase()
+void SettingsErase(uint8_t type)
 {
-  SpiFlashOpResult result;
+  /*
+    0 = Erase from program end until end of physical flash
+    1 = Erase SDK parameter area at end of linker memory model (0x0FDxxx - 0x0FFFFF) solving possible wifi errors
+  */
+
+  bool result;
 
   uint32_t _sectorStart = (ESP.getSketchSize() / SPI_FLASH_SEC_SIZE) + 1;
   uint32_t _sectorEnd = ESP.getFlashChipRealSize() / SPI_FLASH_SEC_SIZE;
+  if (1 == type) {
+    _sectorStart = SETTINGS_LOCATION +2;  // SDK parameter area above EEPROM area (0x0FDxxx - 0x0FFFFF)
+    _sectorEnd = SETTINGS_LOCATION +5;
+  }
+
   boolean _serialoutput = (LOG_LEVEL_DEBUG_MORE <= seriallog_level);
 
   snprintf_P(log_data, sizeof(log_data), PSTR(D_LOG_APPLICATION D_ERASE " %d " D_UNIT_SECTORS), _sectorEnd - _sectorStart);
   AddLog(LOG_LEVEL_DEBUG);
 
   for (uint32_t _sector = _sectorStart; _sector < _sectorEnd; _sector++) {
-    noInterrupts();
-    result = spi_flash_erase_sector(_sector);
-    interrupts();
+    result = ESP.flashEraseSector(_sector);
     if (_serialoutput) {
       Serial.print(F(D_LOG_APPLICATION D_ERASED_SECTOR " "));
       Serial.print(_sector);
-      if (SPI_FLASH_RESULT_OK == result) {
+      if (result) {
         Serial.println(F(" " D_OK));
       } else {
         Serial.println(F(" " D_ERROR));
@@ -352,6 +346,27 @@ void SettingsErase()
   }
 }
 
+// Copied from 2.4.0 as 2.3.0 is incomplete
+bool SettingsEraseConfig(void) {
+  const size_t cfgSize = 0x4000;
+  size_t cfgAddr = ESP.getFlashChipSize() - cfgSize;
+
+  for (size_t offset = 0; offset < cfgSize; offset += SPI_FLASH_SEC_SIZE) {
+    if (!ESP.flashEraseSector((cfgAddr + offset) / SPI_FLASH_SEC_SIZE)) {
+      return false;
+    }
+  }
+  return true;
+}
+
+void SettingsSdkErase()
+{
+  WiFi.disconnect(true);    // Delete SDK wifi config
+  SettingsErase(1);
+  SettingsEraseConfig();
+  delay(1000);
+}
+
 void SettingsDump(char* parms)
 {
   #define CFG_COLS 16
diff --git a/sonoff/sonoff.ino b/sonoff/sonoff.ino
index f0ba58af8..5a669cff0 100644
--- a/sonoff/sonoff.ino
+++ b/sonoff/sonoff.ino
@@ -170,7 +170,7 @@ uint8_t blinkstate = 0;                     // LED state
 
 uint8_t blockgpio0 = 4;                     // Block GPIO0 for 4 seconds after poweron to workaround Wemos D1 RTS circuit
 uint8_t lastbutton[MAX_KEYS] = { NOT_PRESSED, NOT_PRESSED, NOT_PRESSED, NOT_PRESSED };  // Last button states
-uint8_t holdbutton[MAX_KEYS] = { 0 };       // Timer for button hold
+uint16_t holdbutton[MAX_KEYS] = { 0 };      // Timer for button hold
 uint8_t multiwindow[MAX_KEYS] = { 0 };      // Max time between button presses to record press count
 uint8_t multipress[MAX_KEYS] = { 0 };       // Number of button presses within multiwindow
 uint8_t lastwallswitch[MAX_SWITCHES];       // Last wall switch states
@@ -1475,7 +1475,8 @@ void MqttDataCallback(char* topic, byte* data, unsigned int data_len)
         snprintf_P(mqtt_data, sizeof(mqtt_data), S_JSON_COMMAND_SVALUE, command , D_JSON_RESET_AND_RESTARTING);
         break;
       case 2:
-        restart_flag = 212;
+      case 3:
+        restart_flag = 210 + payload;
         snprintf_P(mqtt_data, sizeof(mqtt_data), PSTR("{\"" D_CMND_RESET "\":\"" D_JSON_ERASE ", " D_JSON_RESET_AND_RESTARTING "\"}"));
         break;
       default:
@@ -2370,9 +2371,12 @@ void StateLoop()
       }
     }
     if (restart_flag && (backlog_pointer == backlog_index)) {
-      if (212 == restart_flag) {
-        SettingsErase();
-        restart_flag--;
+      if (213 == restart_flag) {
+        SettingsSdkErase();  // Erase flash SDK parameters
+        restart_flag = 2;
+      } else if (212 == restart_flag) {
+        SettingsErase(0);    // Erase all flash from program end to end of physical flash
+        restart_flag = 211;
       }
       if (211 == restart_flag) {
         SettingsDefault();
diff --git a/sonoff/sonoff_post.h b/sonoff/sonoff_post.h
index 77fc08997..63d5e3c63 100644
--- a/sonoff/sonoff_post.h
+++ b/sonoff/sonoff_post.h
@@ -160,7 +160,7 @@ void WifiWpsStatusCallback(wps_cb_status status);
 
 //#include <core_version.h>                   // Arduino_Esp8266 version information (ARDUINO_ESP8266_RELEASE and ARDUINO_ESP8266_RELEASE_2_3_0)
 #ifndef ARDUINO_ESP8266_RELEASE
-#define ARDUINO_ESP8266_RELEASE "STAGED"
+#define ARDUINO_ESP8266_RELEASE "STAGE"
 #endif
 
 #endif  // _SONOFF_POST_H_
\ No newline at end of file
diff --git a/sonoff/support.ino b/sonoff/support.ino
index f8c706a31..bca8532be 100644
--- a/sonoff/support.ino
+++ b/sonoff/support.ino
@@ -558,10 +558,11 @@ void WifiBegin(uint8_t flag)
 
 #ifdef ARDUINO_ESP8266_RELEASE_2_3_0  // (!strncmp_P(ESP.getSdkVersion(),PSTR("1.5.3"),5))
   AddLog_P(LOG_LEVEL_DEBUG, S_LOG_WIFI, PSTR(D_PATCH_ISSUE_2186));
-  WiFi.mode(WIFI_OFF);    // See https://github.com/esp8266/Arduino/issues/2186
+  WiFi.mode(WIFI_OFF);      // See https://github.com/esp8266/Arduino/issues/2186
 #endif
 
-  WiFi.disconnect();
+  WiFi.disconnect(true);    // Delete SDK wifi config
+  delay(200);
   WiFi.mode(WIFI_STA);      // Disable AP mode
   if (Settings.sleep) {
     WiFi.setSleepMode(WIFI_LIGHT_SLEEP);  // Allow light sleep during idle times
@@ -697,6 +698,7 @@ void WifiCheck(uint8_t param)
         if (WIFI_SMARTCONFIG == wifi_config_type) {
           WiFi.stopSmartConfig();
         }
+        SettingsSdkErase();
         restart_flag = 2;
       }
     } else {