diff --git a/src/_Plugin_Helper.cpp b/src/_Plugin_Helper.cpp
index 5c720cc64..be78161d7 100644
--- a/src/_Plugin_Helper.cpp
+++ b/src/_Plugin_Helper.cpp
@@ -15,6 +15,117 @@
 
 PluginTaskData_base *Plugin_task_data[TASKS_MAX] = {};
 
+#if DEBUG_PCONFIG_RANGE_CHECK
+
+# if DEBUG_PCONFIG_RANGE_CHECK > 2
+#  define DEBUG_PCONFIG_RANGE_CHECK_args   max_n, event, n, linenr, filename
+# elif DEBUG_PCONFIG_RANGE_CHECK > 1
+#  define DEBUG_PCONFIG_RANGE_CHECK_args   max_n, event, n, linenr
+# else
+#  define DEBUG_PCONFIG_RANGE_CHECK_args   max_n, event, n
+# endif
+
+bool PCONFIGxxx_outOfBounds(
+  const __FlashStringHelper   *prefix,
+  const uint8_t                max_n,
+  DEBUG_PCONFIG_RANGE_CHECK_args_decl)
+{
+  if (validTaskIndex(event->TaskIndex) && (n < max_n)) { return false; }
+
+  if (loglevelActiveFor(LOG_LEVEL_ERROR)) {
+    const auto pluginID = getPluginID_from_TaskIndex(event->TaskIndex);
+# if DEBUG_PCONFIG_RANGE_CHECK > 1
+    addLog(LOG_LEVEL_ERROR, strformat(
+             F("%s(%u) out of range (range: 0..%u) for taskIndex %u (%s: %s) (%s:%u)"),
+             FsP(prefix),
+             n,
+             max_n - 1,
+             event->TaskIndex + 1,
+             pluginID.toDisplayString().c_str(),
+             getPluginNameFromPluginID(pluginID).c_str(),
+#  if DEBUG_PCONFIG_RANGE_CHECK > 2
+             FsP(filename),
+#  else
+             FsP(F("line")),
+#  endif
+             linenr));
+# else 
+    addLog(LOG_LEVEL_ERROR, strformat(
+             F("%s(%u) out of range (range: 0..%u) for taskIndex %u (%s: %s)"),
+             FsP(prefix),
+             n,
+             max_n - 1,
+             event->TaskIndex + 1,
+             pluginID.toDisplayString().c_str(),
+             getPluginNameFromPluginID(pluginID).c_str()));
+# endif 
+  }
+  return true;
+}
+
+int16_t& do_PCONFIG(DEBUG_PCONFIG_RANGE_CHECK_args_decl)
+{
+  constexpr uint8_t max_n = NR_ELEMENTS(Settings.TaskDevicePluginConfig[0]);
+
+  if (!PCONFIGxxx_outOfBounds(F("PCONFIG"), DEBUG_PCONFIG_RANGE_CHECK_args)) {
+    return Settings.TaskDevicePluginConfig[event->TaskIndex][n];
+  }
+  static int16_t invalid{};
+  invalid = 0;
+  return invalid;
+}
+
+float& do_PCONFIG_FLOAT(DEBUG_PCONFIG_RANGE_CHECK_args_decl)
+{
+  constexpr uint8_t max_n = NR_ELEMENTS(Settings.TaskDevicePluginConfigFloat[0]);
+
+  if (!PCONFIGxxx_outOfBounds(F("PCONFIG_FLOAT"), DEBUG_PCONFIG_RANGE_CHECK_args)) {
+    return Settings.TaskDevicePluginConfigFloat[event->TaskIndex][n];
+  }
+
+  static float invalid{};
+  invalid = 0;
+  return invalid;
+}
+
+int32_t& do_PCONFIG_LONG(DEBUG_PCONFIG_RANGE_CHECK_args_decl)
+{
+  constexpr uint8_t max_n = NR_ELEMENTS(Settings.TaskDevicePluginConfigLong[0]);
+
+  if (!PCONFIGxxx_outOfBounds(F("PCONFIG_LONG"), DEBUG_PCONFIG_RANGE_CHECK_args)) {
+    return Settings.TaskDevicePluginConfigLong[event->TaskIndex][n];
+  }
+  static int32_t invalid{};
+  invalid = 0;
+  return invalid;
+}
+
+uint32_t& do_PCONFIG_ULONG(DEBUG_PCONFIG_RANGE_CHECK_args_decl)
+{
+  constexpr uint8_t max_n = NR_ELEMENTS(Settings.TaskDevicePluginConfigULong[0]);
+
+  if (!PCONFIGxxx_outOfBounds(F("PCONFIG_ULONG"), DEBUG_PCONFIG_RANGE_CHECK_args)) {
+    return Settings.TaskDevicePluginConfigULong[event->TaskIndex][n];
+  }
+  static uint32_t invalid{};
+  invalid = 0;
+  return invalid;
+}
+
+int8_t& do_PIN(DEBUG_PCONFIG_RANGE_CHECK_args_decl)
+{
+  constexpr uint8_t max_n = 3;
+
+  if (!PCONFIGxxx_outOfBounds(F("PIN"), DEBUG_PCONFIG_RANGE_CHECK_args)) {
+    // N.B. order of array indices taskIndex_t and n differs from the other PCONFIGxxx
+    return Settings.TaskDevicePin[n][event->TaskIndex];
+  }
+  static int8_t invalid{};
+  invalid = -1;
+  return invalid;
+}
+
+#endif // if DEBUG_PCONFIG_RANGE_CHECK
 
 String PCONFIG_LABEL(int n) {
   if (n < PLUGIN_CONFIGVAR_MAX) {
@@ -47,9 +158,9 @@ bool initPluginTaskData(taskIndex_t taskIndex, PluginTaskData_base *data) {
   }
 
   // 2nd heap may have been active to allocate the PluginTaskData, but here we need to keep the default heap active
-  # ifdef USE_SECOND_HEAP
+#ifdef USE_SECOND_HEAP
   HeapSelectDram ephemeral;
-  # endif // ifdef USE_SECOND_HEAP
+#endif // ifdef USE_SECOND_HEAP
 
 
   clearPluginTaskData(taskIndex);
@@ -59,18 +170,20 @@ bool initPluginTaskData(taskIndex_t taskIndex, PluginTaskData_base *data) {
       Plugin_task_data[taskIndex]                     = data;
       Plugin_task_data[taskIndex]->_taskdata_pluginID = Settings.getPluginID_for_task(taskIndex);
 
-  #if FEATURE_PLUGIN_STATS
+#if FEATURE_PLUGIN_STATS
       const uint8_t valueCount = getValueCountForTask(taskIndex);
+
       for (size_t i = 0; i < valueCount; ++i) {
         if (Cache.enabledPluginStats(taskIndex, i)) {
           Plugin_task_data[taskIndex]->initPluginStats(i);
         }
       }
-  #endif
-  #if FEATURE_PLUGIN_FILTER
-  // TODO TD-er: Implement init
+#endif // if FEATURE_PLUGIN_STATS
+#if FEATURE_PLUGIN_FILTER
 
-  #endif
+      // TODO TD-er: Implement init
+
+#endif // if FEATURE_PLUGIN_FILTER
 
     } else {
       delete data;
@@ -81,7 +194,7 @@ bool initPluginTaskData(taskIndex_t taskIndex, PluginTaskData_base *data) {
 
 PluginTaskData_base* getPluginTaskData(taskIndex_t taskIndex) {
   if (pluginTaskData_initialized(taskIndex)) {
-    
+
     if (!Plugin_task_data[taskIndex]->baseClassOnly()) {
       return Plugin_task_data[taskIndex];
     }
@@ -96,7 +209,6 @@ PluginTaskData_base* getPluginTaskDataBaseClassOnly(taskIndex_t taskIndex) {
   return nullptr;
 }
 
-
 bool pluginTaskData_initialized(taskIndex_t taskIndex) {
   if (!validTaskIndex(taskIndex)) {
     return false;
@@ -105,29 +217,22 @@ bool pluginTaskData_initialized(taskIndex_t taskIndex) {
          (Plugin_task_data[taskIndex]->_taskdata_pluginID == Settings.getPluginID_for_task(taskIndex));
 }
 
-String getPluginCustomArgName(int varNr) {
-  return getPluginCustomArgName(F("pc_arg"), varNr);
-}
+String getPluginCustomArgName(int varNr)                                   { return getPluginCustomArgName(F("pc_arg"), varNr); }
 
-String getPluginCustomArgName(const __FlashStringHelper * label, int varNr) {
-  return concat(label, varNr + 1);
-}
+String getPluginCustomArgName(const __FlashStringHelper *label, int varNr) { return concat(label, varNr + 1); }
 
-int getFormItemIntCustomArgName(int varNr) {
-  return getFormItemInt(getPluginCustomArgName(varNr));
-}
+int    getFormItemIntCustomArgName(int varNr)                              { return getFormItemInt(getPluginCustomArgName(varNr)); }
 
 // Helper function to create formatted custom values for display in the devices overview page.
 // When called from PLUGIN_WEBFORM_SHOW_VALUES, the last item should add a traling div_br class
 // if the regular values should also be displayed.
 // The call to PLUGIN_WEBFORM_SHOW_VALUES should only return success = true when no regular values should be displayed
 // Note that the varNr of the custom values should not conflict with the existing variable numbers (e.g. start at VARS_PER_TASK)
-void pluginWebformShowValue(taskIndex_t taskIndex, uint8_t varNr, const __FlashStringHelper * label, const String& value, bool addTrailingBreak) {
-  pluginWebformShowValue(taskIndex, varNr, String(label), value, addTrailingBreak);
-}
+void pluginWebformShowValue(taskIndex_t taskIndex, uint8_t varNr, const __FlashStringHelper *label, const String& value,
+                            bool addTrailingBreak) { pluginWebformShowValue(taskIndex, varNr, String(label), value, addTrailingBreak); }
 
 void pluginWebformShowValue(taskIndex_t   taskIndex,
-                            uint8_t          varNr,
+                            uint8_t       varNr,
                             const String& label,
                             const String& value,
                             bool          addTrailingBreak) {
@@ -175,11 +280,12 @@ bool pluginOptionalTaskIndexArgumentMatch(taskIndex_t taskIndex, const String& s
   return found_taskIndex == taskIndex;
 }
 
-bool pluginWebformShowGPIOdescription(taskIndex_t taskIndex,
-                                      const __FlashStringHelper * newline,
-                                      String& description)
+bool pluginWebformShowGPIOdescription(taskIndex_t                taskIndex,
+                                      const __FlashStringHelper *newline,
+                                      String                   & description)
 {
   struct EventStruct TempEvent(taskIndex);
+
   TempEvent.String1 = newline;
   return PluginCall(PLUGIN_WEBFORM_SHOW_GPIO_DESCR, &TempEvent, description);
 }
@@ -199,6 +305,7 @@ int checkDeviceVTypeForTask(struct EventStruct *event) {
       String dummy;
 
       event->idx = -1;
+
       if (PluginCall(PLUGIN_GET_DEVICEVTYPE, event, dummy)) {
         return event->idx; // pconfig_index
       }
diff --git a/src/_Plugin_Helper.h b/src/_Plugin_Helper.h
index 9848ab0ed..6ebf764e9 100644
--- a/src/_Plugin_Helper.h
+++ b/src/_Plugin_Helper.h
@@ -49,11 +49,11 @@
 #include "src/Helpers/_Plugin_Helper_serial.h"
 
 #if FEATURE_MQTT_DISCOVER
-#include "src/Helpers/_CPlugin_Helper_mqtt.h"
+# include "src/Helpers/_CPlugin_Helper_mqtt.h"
 #endif // if FEATURE_MQTT_DISCOVER
 
 #if FEATURE_PLUGIN_STATS
-#include "src/PluginStructs/_StatsOnly_data_struct.h"
+# include "src/PluginStructs/_StatsOnly_data_struct.h"
 #endif
 
 #include "src/WebServer/Chart_JS.h"
@@ -62,43 +62,111 @@
 #include "src/WebServer/Markup_Forms.h"
 #include "src/WebServer/ESPEasy_WebServer.h"
 
+#if DEBUG_PCONFIG_RANGE_CHECK
+# if DEBUG_PCONFIG_RANGE_CHECK > 2
+#  define DEBUG_PCONFIG_RANGE_CHECK_args_decl   const struct EventStruct *event, uint8_t n, uint16_t linenr, \
+        const __FlashStringHelper *filename
+# elif DEBUG_PCONFIG_RANGE_CHECK > 1
+#  define DEBUG_PCONFIG_RANGE_CHECK_args_decl   const struct EventStruct *event, uint8_t n, uint16_t linenr
+# else // if DEBUG_PCONFIG_RANGE_CHECK > 2
+#  define DEBUG_PCONFIG_RANGE_CHECK_args_decl   const struct EventStruct *event, uint8_t n
+# endif // if DEBUG_PCONFIG_RANGE_CHECK > 2
+
+int16_t & do_PCONFIG(DEBUG_PCONFIG_RANGE_CHECK_args_decl);
+float   & do_PCONFIG_FLOAT(DEBUG_PCONFIG_RANGE_CHECK_args_decl);
+int32_t & do_PCONFIG_LONG(DEBUG_PCONFIG_RANGE_CHECK_args_decl);
+uint32_t& do_PCONFIG_ULONG(DEBUG_PCONFIG_RANGE_CHECK_args_decl);
+int8_t  & do_PIN(DEBUG_PCONFIG_RANGE_CHECK_args_decl);
+#endif // if DEBUG_PCONFIG_RANGE_CHECK
+
 
 // Defines to make plugins more readable.
-
 #ifndef PCONFIG
-  # define PCONFIG(n) (Settings.TaskDevicePluginConfig[event->TaskIndex][(n)])
+# if DEBUG_PCONFIG_RANGE_CHECK
+#  if DEBUG_PCONFIG_RANGE_CHECK > 2
+#   define PCONFIG(n) do_PCONFIG(event, n, __LINE__, F(__FILE__))
+#  elif DEBUG_PCONFIG_RANGE_CHECK > 1
+#   define PCONFIG(n) do_PCONFIG(event, n, __LINE__)
+#  else // if DEBUG_PCONFIG_RANGE_CHECK > 2
+#   define PCONFIG(n) do_PCONFIG(event, n)
+#  endif // if DEBUG_PCONFIG_RANGE_CHECK > 2
+# else // if DEBUG_PCONFIG_RANGE_CHECK
+#  define PCONFIG(n) (Settings.TaskDevicePluginConfig[event->TaskIndex][(n)])
+# endif // if DEBUG_PCONFIG_RANGE_CHECK
 #endif // ifndef PCONFIG
 #ifndef PCONFIG_FLOAT
-  # define PCONFIG_FLOAT(n) (Settings.TaskDevicePluginConfigFloat[event->TaskIndex][(n)])
+# if DEBUG_PCONFIG_RANGE_CHECK
+#  if DEBUG_PCONFIG_RANGE_CHECK > 2
+#   define PCONFIG_FLOAT(n) do_PCONFIG_FLOAT(event, n, __LINE__, F(__FILE__))
+#  elif DEBUG_PCONFIG_RANGE_CHECK > 1
+#   define PCONFIG_FLOAT(n) do_PCONFIG_FLOAT(event, n, __LINE__)
+#  else // if DEBUG_PCONFIG_RANGE_CHECK > 2
+#   define PCONFIG_FLOAT(n) do_PCONFIG_FLOAT(event, n)
+#  endif // if DEBUG_PCONFIG_RANGE_CHECK > 2
+# else // if DEBUG_PCONFIG_RANGE_CHECK
+#  define PCONFIG_FLOAT(n) (Settings.TaskDevicePluginConfigFloat[event->TaskIndex][(n)])
+# endif // if DEBUG_PCONFIG_RANGE_CHECK
 #endif // ifndef PCONFIG_FLOAT
 #ifndef PCONFIG_LONG
-  # define PCONFIG_LONG(n) (Settings.TaskDevicePluginConfigLong[event->TaskIndex][(n)])
+# if DEBUG_PCONFIG_RANGE_CHECK
+#  if DEBUG_PCONFIG_RANGE_CHECK > 2
+#   define PCONFIG_LONG(n) do_PCONFIG_LONG(event, n, __LINE__, F(__FILE__))
+#  elif DEBUG_PCONFIG_RANGE_CHECK > 1
+#   define PCONFIG_LONG(n) do_PCONFIG_LONG(event, n, __LINE__)
+#  else // if DEBUG_PCONFIG_RANGE_CHECK > 2
+#   define PCONFIG_LONG(n) do_PCONFIG_LONG(event, n)
+#  endif // if DEBUG_PCONFIG_RANGE_CHECK > 2
+# else // if DEBUG_PCONFIG_RANGE_CHECK
+#  define PCONFIG_LONG(n) (Settings.TaskDevicePluginConfigLong[event->TaskIndex][(n)])
+# endif // if DEBUG_PCONFIG_RANGE_CHECK
 #endif // ifndef PCONFIG_LONG
 #ifndef PCONFIG_ULONG
-  # define PCONFIG_ULONG(n) (Settings.TaskDevicePluginConfigULong[event->TaskIndex][(n)])
+# if DEBUG_PCONFIG_RANGE_CHECK
+#  if DEBUG_PCONFIG_RANGE_CHECK > 2
+#   define PCONFIG_ULONG(n) do_PCONFIG_ULONG(event, n, __LINE__, F(__FILE__))
+#  elif DEBUG_PCONFIG_RANGE_CHECK > 1
+#   define PCONFIG_ULONG(n) do_PCONFIG_ULONG(event, n, __LINE__)
+#  else // if DEBUG_PCONFIG_RANGE_CHECK > 2
+#   define PCONFIG_ULONG(n) do_PCONFIG_ULONG(event, n)
+#  endif // if DEBUG_PCONFIG_RANGE_CHECK > 2
+# else // if DEBUG_PCONFIG_RANGE_CHECK
+#  define PCONFIG_ULONG(n) (Settings.TaskDevicePluginConfigULong[event->TaskIndex][(n)])
+# endif // if DEBUG_PCONFIG_RANGE_CHECK
 #endif // ifndef PCONFIG_ULONG
 #ifndef PIN
 
 // Please note the 'offset' of N compared to normal pin numbering.
-  # define PIN(n) (Settings.TaskDevicePin[n][event->TaskIndex])
+# if DEBUG_PCONFIG_RANGE_CHECK
+#  if DEBUG_PCONFIG_RANGE_CHECK > 2
+#   define PIN(n) do_PIN(event, n, __LINE__, F(__FILE__))
+#  elif DEBUG_PCONFIG_RANGE_CHECK > 1
+#   define PIN(n) do_PIN(event, n, __LINE__)
+#  else // if DEBUG_PCONFIG_RANGE_CHECK > 2
+#   define PIN(n) do_PIN(event, n)
+#  endif // if DEBUG_PCONFIG_RANGE_CHECK > 2
+# else // if DEBUG_PCONFIG_RANGE_CHECK
+#  define PIN(n) (Settings.TaskDevicePin[n][event->TaskIndex])
+# endif // if DEBUG_PCONFIG_RANGE_CHECK
 #endif // ifndef PIN
 #ifndef CONFIG_PIN1
-  # define CONFIG_PIN1 (Settings.TaskDevicePin1[event->TaskIndex])
+# define CONFIG_PIN1 (Settings.TaskDevicePin1[event->TaskIndex])
 #endif // ifndef CONFIG_PIN1
 #ifndef CONFIG_PIN2
-  # define CONFIG_PIN2 (Settings.TaskDevicePin2[event->TaskIndex])
+# define CONFIG_PIN2 (Settings.TaskDevicePin2[event->TaskIndex])
 #endif // ifndef CONFIG_PIN2
 #ifndef CONFIG_PIN3
-  # define CONFIG_PIN3 (Settings.TaskDevicePin3[event->TaskIndex])
+# define CONFIG_PIN3 (Settings.TaskDevicePin3[event->TaskIndex])
 #endif // ifndef CONFIG_PIN3
 #ifndef CONFIG_PORT
-  # define CONFIG_PORT (Settings.TaskDevicePort[event->TaskIndex])
+# define CONFIG_PORT (Settings.TaskDevicePort[event->TaskIndex])
 #endif // ifndef CONFIG_PORT
 
+
 extern PluginTaskData_base *Plugin_task_data[TASKS_MAX];
 
 // Try to allocate in PSRAM or 2nd heap if possible
-#define special_initPluginTaskData(I, T)  void * ptr = special_calloc(1, sizeof(T)); if (ptr) { initPluginTaskData(I, new (ptr) T()); }
+#define special_initPluginTaskData(I, T) void *ptr = special_calloc(1, sizeof(T)); \
+        if (ptr) { initPluginTaskData(I, new (ptr) T()); }
 
 String PCONFIG_LABEL(int n);
 
@@ -119,7 +187,8 @@ PluginTaskData_base* getPluginTaskDataBaseClassOnly(taskIndex_t taskIndex);
 bool                 pluginTaskData_initialized(taskIndex_t taskIndex);
 
 String               getPluginCustomArgName(int varNr);
-String               getPluginCustomArgName(const __FlashStringHelper * label, int varNr);
+String               getPluginCustomArgName(const __FlashStringHelper *label,
+                                            int                        varNr);
 
 int                  getFormItemIntCustomArgName(int varNr);
 
@@ -128,11 +197,11 @@ int                  getFormItemIntCustomArgName(int varNr);
 // if the regular values should also be displayed.
 // The call to PLUGIN_WEBFORM_SHOW_VALUES should only return success = true when no regular values should be displayed
 // Note that the varNr of the custom values should not conflict with the existing variable numbers (e.g. start at VARS_PER_TASK)
-void pluginWebformShowValue(taskIndex_t   taskIndex,
-                            uint8_t       varNr,
-                            const __FlashStringHelper * label,
-                            const String& value,
-                            bool          addTrailingBreak = false);
+void pluginWebformShowValue(taskIndex_t                taskIndex,
+                            uint8_t                    varNr,
+                            const __FlashStringHelper *label,
+                            const String             & value,
+                            bool                       addTrailingBreak = false);
 
 void pluginWebformShowValue(taskIndex_t   taskIndex,
                             uint8_t       varNr,
@@ -158,9 +227,9 @@ bool pluginOptionalTaskIndexArgumentMatch(taskIndex_t   taskIndex,
                                           const String& string,
                                           uint8_t       paramNr);
 
-bool pluginWebformShowGPIOdescription(taskIndex_t taskIndex, 
-                                      const __FlashStringHelper * newline,
-                                      String& description);
+bool pluginWebformShowGPIOdescription(taskIndex_t                taskIndex,
+                                      const __FlashStringHelper *newline,
+                                      String                   & description);
 
 int getValueCountForTask(taskIndex_t taskIndex);
 
diff --git a/src/src/CustomBuild/define_plugin_sets.h b/src/src/CustomBuild/define_plugin_sets.h
index 127a4cd24..17aea92d2 100644
--- a/src/src/CustomBuild/define_plugin_sets.h
+++ b/src/src/CustomBuild/define_plugin_sets.h
@@ -4651,4 +4651,25 @@ To create/register a plugin, you have to :
 #endif
 #endif // if !FEATURE_SPI && !FEATURE_I2C && !FEATURE_MODBUS && !FEATURE_CAN && !FEATURE_WRMBUS && !FEATURE_WIMBUS
 
+
+
+#ifndef DEBUG_PCONFIG_RANGE_CHECK
+// N.B. Build size increase compared to previous level, based on MAX builds 20260824
+//      Size increase of level 3 depends also on path length of source files.
+// 0: no range check (use for builds with already build size issues)
+// 1: Basic range check, log when out of bounds (+1k)
+// 2: Include line nr of file where error occured (+13k)
+// 3: include filename + path of source file (+23k)
+# ifndef BUILD_NO_DEBUG
+#  ifdef PLUGIN_BUILD_MAX_ESP32
+#   define DEBUG_PCONFIG_RANGE_CHECK 3
+#  else
+#   define DEBUG_PCONFIG_RANGE_CHECK 1
+#  endif
+# else
+#  define DEBUG_PCONFIG_RANGE_CHECK 0
+# endif 
+#endif
+
+
 #endif // CUSTOMBUILD_DEFINE_PLUGIN_SETS_H