diff --git a/examples/companion_radio/MyMesh.cpp b/examples/companion_radio/MyMesh.cpp
index 5d54ad869..348916ca5 100644
--- a/examples/companion_radio/MyMesh.cpp
+++ b/examples/companion_radio/MyMesh.cpp
@@ -1211,7 +1211,9 @@ void MyMesh::handleCmdFrame(size_t len) {
                         ? ERR_CODE_NOT_FOUND
                         : ERR_CODE_UNSUPPORTED_CMD); // unknown recipient, or unsupported TXT_TYPE_*
     }
-  } else if (cmd_frame[0] == CMD_SEND_CHANNEL_TXT_MSG) { // send GroupChannel text msg
+  } else if (cmd_frame[0] == CMD_SEND_CHANNEL_TXT_MSG && len >= 7) { // send GroupChannel text msg
+    // 7 = code, txt_type, channel_idx and the 4 byte timestamp; the text may be empty.
+    // Without this the text length below is computed as len - 7 and turns negative.
     int i = 1;
     uint8_t txt_type = cmd_frame[i++]; // should be TXT_TYPE_PLAIN
     uint8_t channel_idx = cmd_frame[i++];
@@ -2228,7 +2230,8 @@ bool MyMesh::handleCommand(const char* command, uint32_t sender_timestamp, char*
   }
 
   if (strcmp(command, "get tz.offset") == 0) {
-    sprintf(reply, "> %.1f", _prefs.tz_offset);
+    float q = _prefs.tz_offset * 4;
+    sprintf(reply, (q == (int)q && ((int)q & 1)) ? "> %.2f" : "> %.1f", _prefs.tz_offset);
     return true;
   }
   if (memcmp(command, "set tz.offset ", 14) == 0) {
diff --git a/examples/companion_radio/NodePrefs.h b/examples/companion_radio/NodePrefs.h
index 3cceed566..1cc5b5018 100644
--- a/examples/companion_radio/NodePrefs.h
+++ b/examples/companion_radio/NodePrefs.h
@@ -102,8 +102,8 @@ private:
     void setIntThresh(uint8_t t) override { _parent->interference_threshold = t; markDirty(); }
     uint8_t getRxGain() const override { return _parent->rx_boosted_gain; }
     void setRxGain(uint8_t g) override { _parent->rx_boosted_gain = g; markDirty(); }
-    uint8_t getTxPower() const override { return _parent->tx_power_dbm; }
-    void setTxPower(uint8_t dbm) override { _parent->tx_power_dbm = dbm; markDirty(); }
+    int8_t getTxPower() const override { return _parent->tx_power_dbm; }
+    void setTxPower(int8_t dbm) override { _parent->tx_power_dbm = dbm; markDirty(); }
     float getRxDelay() const override { return _parent->rx_delay_base; }
     void setRxDelay(float d) override { _parent->rx_delay_base = d; markDirty(); }
     uint16_t getAgcResetInt() const override { return _parent->agc_reset_interval * 4; }
diff --git a/examples/companion_radio/ui-new/UITask.cpp b/examples/companion_radio/ui-new/UITask.cpp
index d48647b3d..aced739dc 100644
--- a/examples/companion_radio/ui-new/UITask.cpp
+++ b/examples/companion_radio/ui-new/UITask.cpp
@@ -197,11 +197,10 @@ class HomeScreen : public UIScreen {
         sensors_nb ++;
       }
       sensors_scroll = sensors_nb > UI_RECENT_LIST_SIZE;
-#if AUTO_OFF_MILLIS > 0
-      next_sensors_refresh = millis() + 5000; // refresh sensor values every 5 sec
-#else
-      next_sensors_refresh = millis() + 60000; // refresh sensor values every 1 min
-#endif
+      if (display.isEink()) // preserve eink displays
+        next_sensors_refresh = millis() + 60000; // refresh sensor values every 1 min
+      else
+        next_sensors_refresh = millis() + 5000; // refresh sensor values every 5 sec
     }
   }
 
@@ -703,11 +702,7 @@ public:
     display.translateUTF8ToBlocks(filtered_msg, p->msg, sizeof(filtered_msg));
     display.printWordWrap(filtered_msg, display.width());
 
-#if AUTO_OFF_MILLIS==0 // probably e-ink
-    return 10000; // 10 s
-#else
-    return 1000;  // next render after 1000 ms
-#endif
+    return display.isEink() ? 10000 : 1000; // 10 s for eink
   }
 
   bool handleInput(char c) override {
@@ -739,6 +734,9 @@ void UITask::begin(DisplayDriver* display, SensorManager* sensors, NodePrefs* no
 #if defined(PIN_USER_BTN_ANA)
   analog_btn.begin();
 #endif
+#if defined(BACKLIGHT_BTN)
+  backlight_btn.begin();
+#endif
 
   _node_prefs = node_prefs;
 
@@ -910,9 +908,11 @@ void UITask::shutdown(bool restart){
   if (restart) {
     _board->reboot();
   } else {
-    display.forceFullRefresh();
-    display.clear();
-    display.endFrame();
+    if (_display->isEink()) {
+      _display->blankScreen();
+      _display->turnOff();
+      _display->powerOff();
+    }
     // Power off board including radio, display, GPS and components
     _board->powerOff();
   }
@@ -957,7 +957,9 @@ void UITask::loop() {
   if (ev == BUTTON_EVENT_CLICK) {
     c = checkDisplayOn(KEY_ENTER);
   } else if (ev == BUTTON_EVENT_LONG_PRESS) {
+    display.blankScreen();
     display.turnOff();
+    display.powerOff();
   } else if (ev == BUTTON_EVENT_DOUBLE_CLICK) {
     c = handleDoubleClick(KEY_SELECT);
   } else if (ev == BUTTON_EVENT_TRIPLE_CLICK) {
@@ -1002,13 +1004,31 @@ void UITask::loop() {
 #endif
 #if defined(BACKLIGHT_BTN)
   if (millis() > next_backlight_btn_check) {
-    bool touch_state = digitalRead(PIN_BUTTON2);
+    if (backlight_btn.isPressed()) {
+      if (!_display->isOn()) {
+        _display->turnOn();
+        _next_refresh = 0;
+      }
+      _auto_off = millis() + AUTO_OFF_MILLIS;   // extend auto-off timer
+      backlight_btn_pressed_at = millis(); // still pressed
+    }
+    bool touch_state = (millis() - backlight_btn_pressed_at > 5000);
+      // Backlight button events
+    int bev = backlight_btn.check();
+    if (bev == BUTTON_EVENT_DOUBLE_CLICK) {
+      _display->forceFullRefresh();
+    } else if (bev == BUTTON_EVENT_TRIPLE_CLICK) {
+      _display->blankScreen();
+      _display->turnOff();
+      _display->powerOff();
+      backlight_btn_pressed_at = 0;
+    }
 #if defined(DISP_BACKLIGHT)
     digitalWrite(DISP_BACKLIGHT, !touch_state);
 #elif defined(EXP_PIN_BACKLIGHT)
     expander.digitalWrite(EXP_PIN_BACKLIGHT, !touch_state);
 #endif
-    next_backlight_btn_check = millis() + 300;
+    next_backlight_btn_check = millis() + 100;
   }
 #endif
 
@@ -1056,6 +1076,12 @@ void UITask::loop() {
     }
 #endif
     if (millis() > _auto_off) {
+        #ifdef EINK_SCREENOFF_BLANK
+        if (curr != msg_preview) { // don't blank if messages are waiting
+          _display->blankScreen();
+          _display->powerOff();
+        }
+        #endif
       _display->turnOff();
     }
 #endif
diff --git a/examples/companion_radio/ui-new/UITask.h b/examples/companion_radio/ui-new/UITask.h
index 361b04d01..4d44bfe1a 100644
--- a/examples/companion_radio/ui-new/UITask.h
+++ b/examples/companion_radio/ui-new/UITask.h
@@ -61,7 +61,8 @@ class UITask : public AbstractUITask {
   unsigned long _alert_expiry;
   int _msgcount;
   unsigned long ui_started_at, next_batt_chck;
-  int next_backlight_btn_check = 0;
+  unsigned long next_backlight_btn_check = 0;
+  unsigned long backlight_btn_pressed_at = 0;
 #ifdef PIN_STATUS_LED
   int led_state = 0;
   int next_led_change = 0;
diff --git a/examples/kiss_modem/main.cpp b/examples/kiss_modem/main.cpp
index 44b2a3df0..bb77c23d7 100644
--- a/examples/kiss_modem/main.cpp
+++ b/examples/kiss_modem/main.cpp
@@ -115,7 +115,10 @@ void setup() {
   delay(100);
 #if defined(ESP32) && defined(ARDUINO_USB_CDC_ON_BOOT) && ARDUINO_USB_CDC_ON_BOOT
   Serial.setTxTimeoutMs(USB_TX_TIMEOUT_MS);
+#if defined(ARDUINO_USB_MODE) && ARDUINO_USB_MODE
+  // HWCDC only; TinyUSB's USBCDC TX buffer is fixed at build time
   Serial.setTxBufferSize(USB_TX_BUFFER_SIZE);
+#endif
 #endif
   modem = new KissModem(Serial, identity, rng, radio_driver, board, sensors);
 #endif
diff --git a/examples/simple_repeater/MyMesh.cpp b/examples/simple_repeater/MyMesh.cpp
index e8d725f25..7945ef74a 100644
--- a/examples/simple_repeater/MyMesh.cpp
+++ b/examples/simple_repeater/MyMesh.cpp
@@ -258,8 +258,8 @@ int MyMesh::handleRequest(ClientInfo *sender, uint32_t sender_timestamp, uint8_t
     stats.n_recv_direct = getNumRecvDirect();
     stats.err_events = _err_flags;
     stats.last_snr = (int16_t)(radio_driver.getLastSNR() * 4);
-    stats.n_direct_dups = ((SimpleMeshTables *)getTables())->getNumDirectDups();
-    stats.n_flood_dups = ((SimpleMeshTables *)getTables())->getNumFloodDups();
+    stats.n_direct_dups = std::min<uint32_t>(((SimpleMeshTables *)getTables())->getNumDirectDups(), 0xFFFF);
+    stats.n_flood_dups = std::min<uint32_t>(((SimpleMeshTables *)getTables())->getNumFloodDups(), 0xFFFF);
     stats.total_rx_air_time_secs = getReceiveAirTime() / 1000;
     stats.n_recv_errors = radio_driver.getPacketsRecvErrors();
     memcpy(&reply_data[4], &stats, sizeof(stats));
diff --git a/examples/simple_room_server/MyMesh.cpp b/examples/simple_room_server/MyMesh.cpp
index ffa24617b..ba13dc62b 100644
--- a/examples/simple_room_server/MyMesh.cpp
+++ b/examples/simple_room_server/MyMesh.cpp
@@ -1,4 +1,5 @@
 #include "MyMesh.h"
+#include <algorithm>
 
 #define REPLY_DELAY_MILLIS          1500
 #define PUSH_NOTIFY_DELAY_MILLIS    2000
@@ -193,8 +194,8 @@ int MyMesh::handleRequest(ClientInfo *sender, uint32_t sender_timestamp, uint8_t
     stats.n_recv_direct = getNumRecvDirect();
     stats.err_events = _err_flags;
     stats.last_snr = (int16_t)(radio_driver.getLastSNR() * 4);
-    stats.n_direct_dups = ((SimpleMeshTables *)getTables())->getNumDirectDups();
-    stats.n_flood_dups = ((SimpleMeshTables *)getTables())->getNumFloodDups();
+    stats.n_direct_dups = std::min<uint32_t>(((SimpleMeshTables *)getTables())->getNumDirectDups(), 0xFFFF);
+    stats.n_flood_dups = std::min<uint32_t>(((SimpleMeshTables *)getTables())->getNumFloodDups(), 0xFFFF);
     stats.n_posted = _num_posted;
     stats.n_post_push = _num_post_pushes;
 
diff --git a/platformio.ini b/platformio.ini
index f296f8382..92c94204c 100644
--- a/platformio.ini
+++ b/platformio.ini
@@ -19,8 +19,7 @@ monitor_speed = 115200
 lib_deps =
   SPI
   Wire
-  ;jgromes/RadioLib @ ^7.7.1
-  https://github.com/jgromes/RadioLib.git#6d8934836678d8894e3d556550475b37dce3e2b6
+  jgromes/RadioLib @ 7.8.1
   rweather/Crypto @ ^0.4.0
   adafruit/RTClib @ ^2.1.3
   melopero/Melopero RV3028 @ ^1.1.0
diff --git a/src/helpers/BaseChatMesh.cpp b/src/helpers/BaseChatMesh.cpp
index c78d1b64b..b03ddc5a7 100644
--- a/src/helpers/BaseChatMesh.cpp
+++ b/src/helpers/BaseChatMesh.cpp
@@ -167,6 +167,7 @@ void BaseChatMesh::onAdvertRecv(mesh::Packet* packet, const mesh::Identity& id,
 
   ContactInfo* from = NULL;
   for (int i = 0; i < num_contacts; i++) {
+    if (contacts[i].isEmptySlot()) continue;
     if (id.matches(contacts[i].id)) {  // is from one of our contacts
       from = &contacts[i];
       if (timestamp <= from->last_advert_timestamp) {  // check for replay attacks!!
@@ -243,6 +244,11 @@ void BaseChatMesh::onAdvertRecv(mesh::Packet* packet, const mesh::Identity& id,
 int BaseChatMesh::searchPeersByHash(const uint8_t* hash) {
   int n = 0;
   for (int i = 0; i < num_contacts && n < MAX_SEARCH_RESULTS; i++) {
+    // Skip empty/unconfigured anon slots. An empty slot has an all-zero pub_key
+    // (an order-4 Edwards25519 point whose clamped X25519 key exchange yields an
+    // all-zero shared secret for any private key) and would otherwise match
+    // src_hash == 0x00 as a null-key peer sink while consuming search slots.
+    if (contacts[i].isEmptySlot()) continue;
     if (contacts[i].id.isHashMatch(hash)) {
       matching_peer_indexes[n++] = i;  // store the INDEXES of matching contacts (for subsequent 'peer' methods)
     }
@@ -584,6 +590,11 @@ int  BaseChatMesh::sendCommandData(ContactInfo& recipient, uint32_t timestamp, u
 }
 
 bool BaseChatMesh::sendGroupMessage(uint32_t timestamp, mesh::GroupChannel& channel, const char* sender_name, const char* text, int text_len) {
+  if (text_len < 0) {   // memcpy() below would read this as a size_t, so clamping cannot catch it
+    MESH_DEBUG_PRINTLN("sendGroupMessage: invalid negative text_len=%d", text_len);
+    return false;
+  }
+
   uint8_t temp[5+MAX_TEXT_LEN+32];
   memcpy(temp, &timestamp, 4);   // mostly an extra blob to help make packet_hash unique
   temp[4] = 0;  // TXT_TYPE_PLAIN
@@ -916,6 +927,7 @@ ContactInfo* BaseChatMesh::searchContactsByPrefix(const char* name_prefix) {
   int len = strlen(name_prefix);
   for (int i = 0; i < num_contacts; i++) {
     auto c = &contacts[i];
+    if (c->isEmptySlot() || c->name[0] == 0) continue;
     if (memcmp(c->name, name_prefix, len) == 0) return c;
   }
   return NULL;  // not found
@@ -924,6 +936,7 @@ ContactInfo* BaseChatMesh::searchContactsByPrefix(const char* name_prefix) {
 ContactInfo* BaseChatMesh::lookupContactByPubKey(const uint8_t* pub_key, int prefix_len) {
   for (int i = 0; i < num_contacts; i++) {
     auto c = &contacts[i];
+    if (c->isEmptySlot()) continue;
     if (memcmp(c->id.pub_key, pub_key, prefix_len) == 0) return c;
   }
   return NULL;  // not found
@@ -941,7 +954,7 @@ bool BaseChatMesh::addContact(const ContactInfo& contact) {
 
 bool BaseChatMesh::removeContact(ContactInfo& contact) {
   int idx = 0;
-  while (idx < num_contacts && !contacts[idx].id.matches(contact.id)) {
+  while (idx < num_contacts && (contacts[idx].isEmptySlot() || !contacts[idx].id.matches(contact.id))) {
     idx++;
   }
   if (idx >= num_contacts) return false;   // not found
diff --git a/src/helpers/CommonCLI.h b/src/helpers/CommonCLI.h
index 3d218aead..33c8c95ae 100644
--- a/src/helpers/CommonCLI.h
+++ b/src/helpers/CommonCLI.h
@@ -116,8 +116,8 @@ private:
     void setIntThresh(uint8_t t) override { _parent->interference_threshold = t; markDirty(); }
     uint8_t getRxGain() const override { return _parent->rx_boosted_gain; }
     void setRxGain(uint8_t g) override { _parent->rx_boosted_gain = g; markDirty(); }
-    uint8_t getTxPower() const override { return _parent->tx_power_dbm; }
-    void setTxPower(uint8_t dbm) override { _parent->tx_power_dbm = dbm; markDirty(); }
+    int8_t getTxPower() const override { return _parent->tx_power_dbm; }
+    void setTxPower(int8_t dbm) override { _parent->tx_power_dbm = dbm; markDirty(); }
     float getRxDelay() const override { return _parent->rx_delay_base; }
     void setRxDelay(float d) override { _parent->rx_delay_base = d; markDirty(); }
     uint16_t getAgcResetInt() const override { return _parent->agc_reset_interval * 4; }
diff --git a/src/helpers/CommonRadioPrefs.cpp b/src/helpers/CommonRadioPrefs.cpp
index 41b179932..44e0eba31 100644
--- a/src/helpers/CommonRadioPrefs.cpp
+++ b/src/helpers/CommonRadioPrefs.cpp
@@ -2,6 +2,22 @@
 #include "TxtDataHelpers.h"
 #include "Utils.h"
 #include "target.h"
+#include <ctype.h>
+
+namespace {
+
+// strtof() and atof() also read "nan" and "inf". A NaN cannot be refused by a
+// range check: no ordered comparison is true for it, and under -ffast-math,
+// which nRF52 builds use, the compiler may assume it never occurs and fold any
+// test on the parsed value away. So the text is checked before it is parsed:
+// after optional white space and sign, a number starts with a digit or a '.'.
+bool looksLikeANumber(const char* s) {
+  while (isspace((unsigned char)*s)) s++;
+  if (*s == '+' || *s == '-') s++;
+  return isdigit((unsigned char)*s) || *s == '.';
+}
+
+}  // namespace
 
 bool CommonRadioPrefs::getByKey(const char* key, char* value, size_t max_len) {
   if (strcmp(key, "fem_rxgain") == 0) {
@@ -69,7 +85,7 @@ bool CommonRadioPrefs::handleCommand(const char* command, uint32_t sender_timest
   if (memcmp(command, "set af ", 7) == 0) {
     char* end;
     float af = strtof(&command[7], &end);
-    if (end == &command[7] || af < 0 || af > 9) {
+    if (end == &command[7] || !looksLikeANumber(&command[7]) || af < 0 || af > 9) {
       strcpy(reply, "ERROR: af must be 0-9");
     } else {
       setAirtimeFactor(af);
@@ -87,7 +103,7 @@ bool CommonRadioPrefs::handleCommand(const char* command, uint32_t sender_timest
   }
   if (memcmp(command, "set dutycycle ", 14) == 0) {
     float dc = atof(&command[14]);
-    if (dc < 1 || dc > 100) {
+    if (!looksLikeANumber(&command[14]) || dc < 1 || dc > 100) {
       strcpy(reply, "ERROR: dutycycle must be 1-100");
     } else {
       setAirtimeFactor((100.0f / dc) - 1.0f);
diff --git a/src/helpers/CommonRadioPrefs.h b/src/helpers/CommonRadioPrefs.h
index 0e83ca9df..d0083b8c7 100644
--- a/src/helpers/CommonRadioPrefs.h
+++ b/src/helpers/CommonRadioPrefs.h
@@ -35,8 +35,8 @@ public:
   virtual uint8_t getRxGain() const = 0;
   virtual void setRxGain(uint8_t g) = 0;
 
-  virtual uint8_t getTxPower() const = 0;
-  virtual void setTxPower(uint8_t dbm) = 0;
+  virtual int8_t getTxPower() const = 0;
+  virtual void setTxPower(int8_t dbm) = 0;
 
   virtual float getRxDelay() const = 0;
   virtual void setRxDelay(float d) = 0;
diff --git a/src/helpers/ContactInfo.h b/src/helpers/ContactInfo.h
index f93fea77a..5f431bdaf 100644
--- a/src/helpers/ContactInfo.h
+++ b/src/helpers/ContactInfo.h
@@ -34,6 +34,12 @@ struct ContactInfo {
   bool isTelemLocAllowed() const { return flags & 0x04; }
   bool isTelemEnvAllowed() const { return flags & 0x08; }
   bool isRemoteCLIAllowed() const { return flags & 0x10; }
+  bool isEmptySlot() const {
+    for (int i = 0; i < PUB_KEY_SIZE; i++) {
+      if (id.pub_key[i] != 0) return false;
+    }
+    return true;
+  }
 
 private:
   mutable uint8_t shared_secret[PUB_KEY_SIZE];
diff --git a/src/helpers/ESP32Board.cpp b/src/helpers/ESP32Board.cpp
index a55abb264..d190fca19 100644
--- a/src/helpers/ESP32Board.cpp
+++ b/src/helpers/ESP32Board.cpp
@@ -3,6 +3,10 @@
 #include "ESP32Board.h"
 #include <target.h>
 
+// The RTC backup of ESP32RTCClock, declared in ESP32Board.h.
+RTC_NOINIT_ATTR uint32_t _rtc_backup_time;
+RTC_NOINIT_ATTR uint32_t _rtc_backup_magic;
+
 #if defined(ADMIN_PASSWORD) && !defined(DISABLE_WIFI_OTA)   // Repeater or Room Server only
 #include <WiFi.h>
 #include <AsyncTCP.h>
diff --git a/src/helpers/ESP32Board.h b/src/helpers/ESP32Board.h
index 3f95e6923..cd274cd93 100644
--- a/src/helpers/ESP32Board.h
+++ b/src/helpers/ESP32Board.h
@@ -200,8 +200,11 @@ public:
   }
 };
 
-static RTC_NOINIT_ATTR uint32_t _rtc_backup_time;
-static RTC_NOINIT_ATTR uint32_t _rtc_backup_magic;
+// The time ESP32RTCClock restores after a reset, in RTC memory that a reset does
+// not clear. Defined once, in ESP32Board.cpp: the inline members below run in
+// every translation unit that uses them and must all see the same backup.
+extern uint32_t _rtc_backup_time;
+extern uint32_t _rtc_backup_magic;
 #define RTC_BACKUP_MAGIC  0xAA55CC33
 #define RTC_TIME_MIN      1772323200  // 1 Mar 2026
 
diff --git a/src/helpers/RegionMap.cpp b/src/helpers/RegionMap.cpp
index d8d773803..16a8e1ff9 100644
--- a/src/helpers/RegionMap.cpp
+++ b/src/helpers/RegionMap.cpp
@@ -188,7 +188,7 @@ int RegionMap::getTransportKeysFor(const RegionEntry& src, TransportKey dest[],
 }
 
 RegionEntry* RegionMap::findMatch(mesh::Packet* packet, uint8_t mask) {
-  if (packet->transport_codes[0] == 0) return &wildcard;
+  if (packet->transport_codes[0] == 0) return (wildcard.flags & mask) == 0 ? &wildcard : NULL;
   for (int i = 0; i < num_regions; i++) {
     auto region = &regions[i];
     if ((region->flags & mask) == 0) {   // does region allow this? (per 'mask' param)
diff --git a/src/helpers/RoutingPolicy.h b/src/helpers/RoutingPolicy.h
index 5251a590a..225e5cd48 100644
--- a/src/helpers/RoutingPolicy.h
+++ b/src/helpers/RoutingPolicy.h
@@ -17,6 +17,7 @@ inline bool isFloodHopLimitExceeded(const Packet* packet, uint8_t flood_max,
   uint8_t hops = packet->getPathHashCount();
   if (hops >= flood_max) return true;
   if (packet->getRouteType() == ROUTE_TYPE_FLOOD && hops >= flood_max_unscoped) return true;
+  if (packet->getRouteType() == ROUTE_TYPE_TRANSPORT_FLOOD && packet->transport_codes[0] == 0 && hops >= flood_max_unscoped) return true;  // scope 0, treat as unscoped
   if (packet->getPayloadType() == PAYLOAD_TYPE_ADVERT && hops >= flood_max_advert) return true;
   return false;
 }
diff --git a/src/helpers/radiolib/CustomLR2021Wrapper.h b/src/helpers/radiolib/CustomLR2021Wrapper.h
index 8299e2bf5..c60bfda3d 100644
--- a/src/helpers/radiolib/CustomLR2021Wrapper.h
+++ b/src/helpers/radiolib/CustomLR2021Wrapper.h
@@ -16,15 +16,23 @@ public:
   CustomLR2021Wrapper(CustomLR2021& radio, mesh::MainBoard& board) : RadioLibWrapper(radio, board) { }
 
   void setParams(float freq, float bw, uint8_t sf, uint8_t cr) override {
-    ((CustomLR2021 *)_radio)->setFrequency(freq);
-    ((CustomLR2021 *)_radio)->setSpreadingFactor(sf);
-    ((CustomLR2021 *)_radio)->setBandwidth(bw);
-    ((CustomLR2021 *)_radio)->setCodingRate(cr);
+    auto r = (CustomLR2021 *)_radio;
+    // LR2021 only accepts RF/modulation config commands while in STANDBY mode.
+    // Re-configuring while in continuous RX gets silently rejected (-706),
+    // which broke hot frequency changes over BLE.
+    int16_t status = r->standby();
+    if (status != RADIOLIB_ERR_NONE) { MESH_DEBUG_PRINTLN("CustomLR2021Wrapper: standby() -> %d", status); }
+    if ((status = r->setFrequency(freq)) != RADIOLIB_ERR_NONE) { MESH_DEBUG_PRINTLN("CustomLR2021Wrapper: setFrequency() -> %d", status); }
+    if ((status = r->setSpreadingFactor(sf)) != RADIOLIB_ERR_NONE) { MESH_DEBUG_PRINTLN("CustomLR2021Wrapper: setSpreadingFactor() -> %d", status); }
+    if ((status = r->setBandwidth(bw)) != RADIOLIB_ERR_NONE) { MESH_DEBUG_PRINTLN("CustomLR2021Wrapper: setBandwidth() -> %d", status); }
+    if ((status = r->setCodingRate(cr)) != RADIOLIB_ERR_NONE) { MESH_DEBUG_PRINTLN("CustomLR2021Wrapper: setCodingRate() -> %d", status); }
     updatePreamble(sf);
-    applySideDetectorConfig();
+    // internal idle() sets STATE_IDLE, which triggers a startReceive() on the next loop
+    status = applySideDetectorConfig();
+    if (status != RADIOLIB_ERR_NONE) { MESH_DEBUG_PRINTLN("CustomLR2021Wrapper: applySideDetectorConfig() -> %d", status); }
     PacketMillis pm = calcMaxPacketMillis(sf, bw, cr, preambleLengthForSF(sf));
-    ((CustomLR2021 *)_radio)->setPreambleMillis(pm.preambleMillis);
-    ((CustomLR2021 *)_radio)->setMaxPayloadMillis(pm.payloadMillis);
+    r->setPreambleMillis(pm.preambleMillis);      // pure in-memory setters, no standby needed
+    r->setMaxPayloadMillis(pm.payloadMillis);
 
   }
 
diff --git a/src/helpers/ui/AutoDetectDisplay.cpp b/src/helpers/ui/AutoDetectDisplay.cpp
new file mode 100644
index 000000000..e3537ab25
--- /dev/null
+++ b/src/helpers/ui/AutoDetectDisplay.cpp
@@ -0,0 +1,45 @@
+#include "AutoDetectDisplay.h"
+#include <MeshCore.h>
+
+int AutoDetectDisplay::getDisplayStatus(TwoWire& wire, uint8_t addr) {
+  int status = -1;
+  for(int i = 0; i < 4; i++){
+
+    // request display status
+    wire.beginTransmission(addr);
+    wire.write((uint8_t)0x00);
+
+    // ensure response received
+    if (wire.endTransmission() != 0) return -1; // expect success
+    if (wire.requestFrom((int)addr, 1) == 0) return -1; // expect at least 1 byte
+
+    // ensure two consecutive reads are the same
+    int previous = status;
+    status = wire.read() & 0x0F;
+    if(status == previous){
+      break;
+    }
+
+  }
+  return status;
+}
+
+bool AutoDetectDisplay::begin() {
+
+  // request status from display address
+  int status = getDisplayStatus(Wire, DISPLAY_ADDRESS);
+  MESH_DEBUG_PRINTLN("AutoDetectDisplay: status=0x%02X", status);
+
+  // detect SH1106
+  if(status == 0x00 || status == 0x08){
+    MESH_DEBUG_PRINTLN("AutoDetectDisplay: SH1106 detected");
+    _impl = &_sh1106;
+    return _sh1106.begin();
+  }
+
+  // fallback to SSD1306
+  MESH_DEBUG_PRINTLN("AutoDetectDisplay: falling back to SSD1306");
+  _impl = &_ssd1306;
+  return _ssd1306.begin();
+
+}
diff --git a/src/helpers/ui/AutoDetectDisplay.h b/src/helpers/ui/AutoDetectDisplay.h
new file mode 100644
index 000000000..7208d4f59
--- /dev/null
+++ b/src/helpers/ui/AutoDetectDisplay.h
@@ -0,0 +1,32 @@
+#pragma once
+
+#include "DisplayDriver.h"
+#include "SSD1306Display.h"
+#include "SH1106Display.h"
+
+// Auto detects SH1106 display at runtime, otherwise falls back to using SSD1306
+class AutoDetectDisplay : public DisplayDriver {
+  DisplayDriver* _impl;
+  SSD1306Display _ssd1306;
+  SH1106Display _sh1106;
+
+  int getDisplayStatus(TwoWire& wire, uint8_t addr);
+public:
+  AutoDetectDisplay() : DisplayDriver(128, 64), _impl(&_ssd1306) { }
+  bool begin();
+
+  bool isOn() override { return _impl->isOn(); }
+  void turnOn() override { _impl->turnOn(); }
+  void turnOff() override { _impl->turnOff(); }
+  void clear() override { _impl->clear(); }
+  void startFrame(ColorVal bkg = UIColor::window_bkg) override { _impl->startFrame(bkg); }
+  void setTextSize(int sz) override { _impl->setTextSize(sz); }
+  void setColor(ColorVal c) override { _impl->setColor(c); }
+  void setCursor(int x, int y) override { _impl->setCursor(x, y); }
+  void print(const char* str) override { _impl->print(str); }
+  void fillRect(int x, int y, int w, int h) override { _impl->fillRect(x, y, w, h); }
+  void drawRect(int x, int y, int w, int h) override { _impl->drawRect(x, y, w, h); }
+  void drawXbm(int x, int y, const uint8_t* bits, int w, int h) override { _impl->drawXbm(x, y, bits, w, h); }
+  uint16_t getTextWidth(const char* str) override { return _impl->getTextWidth(str); }
+  void endFrame() override { _impl->endFrame(); }
+};
diff --git a/src/helpers/ui/DisplayDriver.h b/src/helpers/ui/DisplayDriver.h
index 3e9e2dde8..58147aa0e 100644
--- a/src/helpers/ui/DisplayDriver.h
+++ b/src/helpers/ui/DisplayDriver.h
@@ -26,6 +26,8 @@ public:
   virtual void forceFullRefresh() {} // next refresh will be full for eink
   virtual void turnOn() = 0;
   virtual void turnOff() = 0;
+  virtual void blankScreen() {} // to cleanly erase screen before turning off
+  virtual void powerOff() {}
   virtual void clear() = 0;
   virtual void startFrame(ColorVal bkg = UIColor::window_bkg) = 0;
   virtual void setTextSize(int sz) = 0;
diff --git a/src/helpers/ui/GxEPDDisplay.cpp b/src/helpers/ui/GxEPDDisplay.cpp
index 332157eb8..ce09423e1 100644
--- a/src/helpers/ui/GxEPDDisplay.cpp
+++ b/src/helpers/ui/GxEPDDisplay.cpp
@@ -75,20 +75,27 @@ void GxEPDDisplay::turnOn() {
   }
 }
 
-void GxEPDDisplay::turnOff() {
+void GxEPDDisplay::powerOff() {
+  display.hibernate();
+}
+
+void GxEPDDisplay::turnOff() { // Only stops refresh
 #if defined(DISP_BACKLIGHT) && !defined(BACKLIGHT_BTN)
   digitalWrite(DISP_BACKLIGHT, LOW);
 #elif defined(EXP_PIN_BACKLIGHT) && !defined(BACKLIGHT_BTN)
   expander.digitalWrite(EXP_PIN_BACKLIGHT, LOW);
 #endif
   _isOn = false;
+  last_display_crc_value=0;
+}
+
+void GxEPDDisplay::blankScreen() {
   // do full refresh before powering off to clear screen
   // no full refresh needed at wakeup
   display.clearScreen(0xFF); // Clears microcontroller side RAM
   display.writeScreenBuffer(0xFF); // Forces 0xFF (White) into the display controller's history registers
   resetPartialRefreshCounter();
   last_display_crc_value=0;
-  display.hibernate();
 }
 
 void GxEPDDisplay::clear() {
diff --git a/src/helpers/ui/GxEPDDisplay.h b/src/helpers/ui/GxEPDDisplay.h
index 8a37b72cc..462744026 100644
--- a/src/helpers/ui/GxEPDDisplay.h
+++ b/src/helpers/ui/GxEPDDisplay.h
@@ -60,6 +60,8 @@ public:
   void resetPartialRefreshCounter() { _cycles_before_full_refresh = max_partial_refresh; };
   void turnOn() override;
   void turnOff() override;
+  void blankScreen() override;
+  void powerOff() override;
   void clear() override;
   void startFrame(ColorVal bkg = UIColor::window_bkg) override;
   void setTextSize(int sz) override;
diff --git a/src/helpers/ui/SH1106Display.cpp b/src/helpers/ui/SH1106Display.cpp
index 8b91d857c..e290b3556 100644
--- a/src/helpers/ui/SH1106Display.cpp
+++ b/src/helpers/ui/SH1106Display.cpp
@@ -10,15 +10,15 @@ bool SH1106Display::i2c_probe(TwoWire &wire, uint8_t addr)
 }
 
 // Color scheme
-ColorVal UIColor::window_bkg = SH110X_BLACK;
-ColorVal UIColor::title_bkg = SH110X_BLACK;
-ColorVal UIColor::title_txt = SH110X_WHITE;
-ColorVal UIColor::primary_txt = SH110X_WHITE;
-ColorVal UIColor::secondary_txt = SH110X_WHITE;
-ColorVal UIColor::warning_txt = SH110X_WHITE;
-ColorVal UIColor::popup_bkg = SH110X_BLACK;
-ColorVal UIColor::popup_txt = SH110X_WHITE;
-ColorVal UIColor::corp_blue = SH110X_WHITE;
+__attribute__((weak)) ColorVal UIColor::window_bkg = SH110X_BLACK;
+__attribute__((weak)) ColorVal UIColor::title_bkg = SH110X_BLACK;
+__attribute__((weak)) ColorVal UIColor::title_txt = SH110X_WHITE;
+__attribute__((weak)) ColorVal UIColor::primary_txt = SH110X_WHITE;
+__attribute__((weak)) ColorVal UIColor::secondary_txt = SH110X_WHITE;
+__attribute__((weak)) ColorVal UIColor::warning_txt = SH110X_WHITE;
+__attribute__((weak)) ColorVal UIColor::popup_bkg = SH110X_BLACK;
+__attribute__((weak)) ColorVal UIColor::popup_txt = SH110X_WHITE;
+__attribute__((weak)) ColorVal UIColor::corp_blue = SH110X_WHITE;
 
 bool SH1106Display::begin()
 {
diff --git a/test/test_empty_contact_slots/test_empty_contact_slots.cpp b/test/test_empty_contact_slots/test_empty_contact_slots.cpp
new file mode 100644
index 000000000..cb4d5912f
--- /dev/null
+++ b/test/test_empty_contact_slots/test_empty_contact_slots.cpp
@@ -0,0 +1,230 @@
+#include <gtest/gtest.h>
+#include <cstring>
+#include <ed_25519.h>
+
+#include "Dispatcher.cpp"
+#include "Mesh.cpp"
+#include "helpers/AdvertDataHelpers.cpp"
+#include "helpers/BaseChatMesh.cpp"
+
+void StrHelper::strncpy(char* dest, const char* src, size_t buf_sz) {
+  if (buf_sz == 0) return;
+  std::strncpy(dest, src, buf_sz - 1);
+  dest[buf_sz - 1] = 0;
+}
+
+namespace mesh {
+
+Identity::Identity() {
+  memset(pub_key, 0, sizeof(pub_key));
+}
+
+bool Identity::verify(const uint8_t*, const uint8_t*, int) const {
+  return true;
+}
+
+LocalIdentity::LocalIdentity() : Identity() {
+  memset(prv_key, 0, sizeof(prv_key));
+}
+
+void LocalIdentity::sign(uint8_t* sig, const uint8_t*, int) const {
+  memset(sig, 0, SIGNATURE_SIZE);
+}
+
+void LocalIdentity::calcSharedSecret(uint8_t* secret, const uint8_t* other_pub_key) const {
+  ed25519_key_exchange(secret, other_pub_key, prv_key);
+}
+
+}  // namespace mesh
+
+namespace {
+
+class DummyRadio : public mesh::Radio {
+public:
+  int recvRaw(uint8_t*, int) override { return 0; }
+  uint32_t getEstAirtimeFor(int) override { return 10; }
+  float packetScore(float, int) override { return 1.0f; }
+  bool startSendRaw(const uint8_t*, int) override { return true; }
+  bool isSendComplete() override { return true; }
+  void onSendFinished() override {}
+  bool isInRecvMode() const override { return true; }
+};
+
+class DummyMillisecondClock : public mesh::MillisecondClock {
+public:
+  unsigned long getMillis() override { return 1000; }
+};
+
+class DummyRNG : public mesh::RNG {
+public:
+  void random(uint8_t* dest, size_t len) override { memset(dest, 0x42, len); }
+};
+
+class DummyRTCClock : public mesh::RTCClock {
+  uint32_t _now = 1700000000;
+public:
+  uint32_t getCurrentTime() override { return _now; }
+  void setCurrentTime(uint32_t time) override { _now = time; }
+};
+
+class DummyPacketManager : public mesh::PacketManager {
+public:
+  mesh::Packet* allocNew() override { return nullptr; }
+  void free(mesh::Packet*) override {}
+  void queueOutbound(mesh::Packet*, uint8_t, uint32_t) override {}
+  mesh::Packet* getNextOutbound(uint32_t) override { return nullptr; }
+  int getOutboundCount(uint32_t) const override { return 0; }
+  int getOutboundTotal() const override { return 0; }
+  int getFreeCount() const override { return 16; }
+  mesh::Packet* getOutboundByIdx(int) override { return nullptr; }
+  mesh::Packet* removeOutboundByIdx(int) override { return nullptr; }
+  void queueInbound(mesh::Packet*, uint32_t) override {}
+  mesh::Packet* getNextInbound(uint32_t) override { return nullptr; }
+};
+
+class DummyMeshTables : public mesh::MeshTables {
+public:
+  bool wasSeen(const mesh::Packet*) override { return false; }
+  void markSeen(const mesh::Packet*) override {}
+  void clear(const mesh::Packet*) override {}
+};
+
+class TestChatMesh : public BaseChatMesh {
+public:
+  int messages_received = 0;
+
+  TestChatMesh(mesh::Radio& radio, mesh::MillisecondClock& ms, mesh::RNG& rng,
+               mesh::RTCClock& rtc, mesh::PacketManager& mgr, mesh::MeshTables& tables)
+      : BaseChatMesh(radio, ms, rng, rtc, mgr, tables) {}
+
+  void onDiscoveredContact(ContactInfo&, bool, uint8_t, const uint8_t*) override {}
+  ContactInfo* processAck(const uint8_t*) override { return nullptr; }
+  void onContactPathUpdated(const ContactInfo&) override {}
+  void onMessageRecv(const ContactInfo&, mesh::Packet*, uint32_t, const char*) override {
+    messages_received++;
+  }
+  void onCommandDataRecv(const ContactInfo&, mesh::Packet*, uint32_t, const char*) override {}
+  void onCLICommandRecv(const ContactInfo&, mesh::Packet*, uint32_t, const char*, char*) override {}
+  void onSignedMessageRecv(const ContactInfo&, mesh::Packet*, uint32_t, const uint8_t*, const char*) override {}
+  void onChannelMessageRecv(const mesh::GroupChannel&, mesh::Packet*, uint32_t, const char*) override {}
+  uint8_t onContactRequest(const ContactInfo&, uint32_t, const uint8_t*, uint8_t, uint8_t*) override { return 0; }
+  void onContactResponse(const ContactInfo&, const uint8_t*, uint8_t) override {}
+  uint32_t calcFloodTimeoutMillisFor(uint32_t) const override { return 1000; }
+  uint32_t calcDirectTimeoutMillisFor(uint32_t, uint8_t) const override { return 1000; }
+  void onSendTimeout() override {}
+
+  using BaseChatMesh::resetContacts;
+  using BaseChatMesh::searchPeersByHash;
+  using BaseChatMesh::getPeerSharedSecret;
+  using mesh::Mesh::onRecvPacket;
+};
+
+struct MeshFixture {
+  DummyRadio radio;
+  DummyMillisecondClock ms;
+  DummyRNG rng;
+  DummyRTCClock rtc;
+  DummyPacketManager mgr;
+  DummyMeshTables tables;
+  TestChatMesh chat{radio, ms, rng, rtc, mgr, tables};
+};
+
+}  // namespace
+
+TEST(EmptyContactSlots, ZeroPubKeyProducesAllZeroSharedSecretForAnyPrivateKey) {
+  ContactInfo empty_slot;
+  memset(&empty_slot, 0, sizeof(empty_slot));
+  EXPECT_TRUE(empty_slot.isEmptySlot());
+
+  uint8_t raw_prv[PRV_KEY_SIZE];
+  for (int i = 0; i < PRV_KEY_SIZE; i++) {
+    raw_prv[i] = static_cast<uint8_t>(0xA5 ^ (i * 13 + 7));
+  }
+  uint8_t secret[PUB_KEY_SIZE];
+  ed25519_key_exchange(secret, empty_slot.id.pub_key, raw_prv);
+
+  uint8_t expected_zeroes[PUB_KEY_SIZE] = { 0 };
+  EXPECT_EQ(0, memcmp(secret, expected_zeroes, PUB_KEY_SIZE));
+}
+
+TEST(EmptyContactSlots, NullKeyPeerPacketIsRejectedWhenAnonSlotsAreEmpty) {
+  MeshFixture fx;
+  fx.chat.self_id.pub_key[0] = 0x42;
+
+  // Craft a PAYLOAD_TYPE_TXT_MSG addressed to self_id (dest_hash=0x42) with src_hash=0x00,
+  // encrypted and MAC'd under the all-zero 32-byte key that an empty ContactInfo slot derives.
+  uint8_t zero_secret[PUB_KEY_SIZE] = { 0 };
+  uint8_t plaintext[16] = { 0 };
+  uint32_t ts = 1700000001;
+  memcpy(plaintext, &ts, 4);
+  plaintext[4] = (TXT_TYPE_PLAIN << 2);
+  strcpy(reinterpret_cast<char*>(&plaintext[5]), "forged");
+
+  mesh::Packet pkt;
+  pkt.header = ROUTE_TYPE_FLOOD | (PAYLOAD_TYPE_TXT_MSG << PH_TYPE_SHIFT);
+  pkt.path_len = 0;
+  pkt.payload[0] = 0x42;  // dest_hash (matches fx.chat.self_id)
+  pkt.payload[1] = 0x00;  // src_hash (matches all-zero pub_key if empty slots are not skipped)
+  int enc_len = mesh::Utils::encryptThenMAC(zero_secret, &pkt.payload[2], plaintext, 12);
+  pkt.payload_len = static_cast<uint8_t>(2 + enc_len);
+
+  fx.chat.onRecvPacket(&pkt);
+  EXPECT_EQ(0, fx.chat.messages_received);
+}
+
+TEST(EmptyContactSlots, SearchPeersByHashSkipsEmptyAnonSlotsAndFindsRealZeroPrefixPeer) {
+  MeshFixture fx;
+  const uint8_t zero_hash = 0x00;
+
+  // Freshly reset contacts has MAX_ANON_CONTACTS (8) zeroed transient slots.
+  EXPECT_EQ(0, fx.chat.searchPeersByHash(&zero_hash));
+
+  // Add a legitimate permanent contact whose public key starts with 0x00.
+  ContactInfo peer;
+  memset(&peer, 0, sizeof(peer));
+  peer.type = ADV_TYPE_CHAT;
+  peer.lastmod = 1700000100;
+  strcpy(peer.name, "Alice");
+  peer.id.pub_key[0] = 0x00;
+  for (int i = 1; i < PUB_KEY_SIZE; i++) {
+    peer.id.pub_key[i] = static_cast<uint8_t>(i);
+  }
+  ASSERT_TRUE(fx.chat.addContact(peer));
+
+  // Only the populated contact at index MAX_ANON_CONTACTS should match.
+  EXPECT_EQ(1, fx.chat.searchPeersByHash(&zero_hash));
+
+  // Lookup by pubkey and name prefix must also skip the empty transient slots.
+  uint8_t zero_prefix[6] = { 0 };
+  EXPECT_EQ(nullptr, fx.chat.lookupContactByPubKey(zero_prefix, sizeof(zero_prefix)));
+
+  ContactInfo* found = fx.chat.lookupContactByPubKey(peer.id.pub_key, 6);
+  ASSERT_NE(nullptr, found);
+  EXPECT_STREQ("Alice", found->name);
+
+  ContactInfo* by_name = fx.chat.searchContactsByPrefix("");
+  ASSERT_NE(nullptr, by_name);
+  EXPECT_STREQ("Alice", by_name->name);
+}
+
+TEST(EmptyContactSlots, PopulatedTransientAnonSlotStillMatchesEvenWhenLastmodIsZero) {
+  MeshFixture fx;
+  const uint8_t zero_hash = 0x00;
+
+  ContactInfo anon;
+  memset(&anon, 0, sizeof(anon));
+  anon.type = ADV_TYPE_NONE;
+  anon.lastmod = 0;  // e.g. RTC not yet initialised on nRF52
+  anon.id.pub_key[0] = 0x00;
+  anon.id.pub_key[1] = 0x7F;
+  ASSERT_TRUE(fx.chat.addContact(anon));
+
+  EXPECT_FALSE(anon.isEmptySlot());
+  EXPECT_EQ(1, fx.chat.searchPeersByHash(&zero_hash));
+  EXPECT_NE(nullptr, fx.chat.lookupContactByPubKey(anon.id.pub_key, PUB_KEY_SIZE));
+}
+
+int main(int argc, char** argv) {
+  ::testing::InitGoogleTest(&argc, argv);
+  return RUN_ALL_TESTS();
+}
diff --git a/test/test_routing_policy/test_routing_policy.cpp b/test/test_routing_policy/test_routing_policy.cpp
index bba9ec790..3f7faf305 100644
--- a/test/test_routing_policy/test_routing_policy.cpp
+++ b/test/test_routing_policy/test_routing_policy.cpp
@@ -8,6 +8,9 @@ static Packet makeFlood(uint8_t route_type, uint8_t payload_type, uint8_t hops)
     p.header = route_type | (payload_type << PH_TYPE_SHIFT);
     p.setPathHashSizeAndCount(1, hops);
     p.payload_len = 1;
+    if (route_type == ROUTE_TYPE_TRANSPORT_FLOOD) {
+        p.transport_codes[0] = 1;  // has to be non-zero
+    }
     return p;
 }
 
diff --git a/variants/heltec_v4/platformio.ini b/variants/heltec_v4/platformio.ini
index 76e8e714e..c91e31a80 100644
--- a/variants/heltec_v4/platformio.ini
+++ b/variants/heltec_v4/platformio.ini
@@ -380,12 +380,14 @@ build_flags =
   -D AUTO_SHUTDOWN_MILLIVOLTS=3400
   -D BLE_DEBUG_LOGGING=1
   -D OFFLINE_QUEUE_SIZE=256
+  -D ENABLE_WIFI_INTERFACE
 ;  -D MESH_PACKET_LOGGING=1
 ;  -D MESH_DEBUG=1
 build_src_filter = ${heltec_v4_tft.build_src_filter}
   +<helpers/ui/ST7789LCDDisplay.cpp>
   +<helpers/ui/MomentaryButton.cpp>
   +<helpers/esp32/*.cpp>
+  +<helpers/wifi/*.cpp>
   +<../examples/companion_radio/*.cpp>
   +<../examples/companion_radio/ui-new/*.cpp>
 lib_deps =
diff --git a/variants/lilygo_tbeam_supreme_SX1262/platformio.ini b/variants/lilygo_tbeam_supreme_SX1262/platformio.ini
index af4a8eafa..18a828025 100644
--- a/variants/lilygo_tbeam_supreme_SX1262/platformio.ini
+++ b/variants/lilygo_tbeam_supreme_SX1262/platformio.ini
@@ -131,11 +131,13 @@ build_flags =
   -D MAX_GROUP_CHANNELS=40
   -D BLE_PIN_CODE=123456
   -D OFFLINE_QUEUE_SIZE=256
+  -D ENABLE_WIFI_INTERFACE
 ;  -D BLE_DEBUG_LOGGING=1
 ;  -D MESH_PACKET_LOGGING=8
 ;  -D MESH_DEBUG=1
 build_src_filter = ${T_Beam_S3_Supreme_SX1262.build_src_filter}
   +<helpers/esp32/*.cpp>
+  +<helpers/wifi/*.cpp>
   +<helpers/ui/MomentaryButton.cpp>
   +<../examples/companion_radio/*.cpp>
   +<../examples/companion_radio/ui-new/*.cpp>
diff --git a/variants/lilygo_techo/platformio.ini b/variants/lilygo_techo/platformio.ini
index 81da2e48c..ba39549e1 100644
--- a/variants/lilygo_techo/platformio.ini
+++ b/variants/lilygo_techo/platformio.ini
@@ -32,8 +32,17 @@ build_flags = ${nrf52_base.build_flags}
   -D PIN_GPS_RESET_ACTIVE=LOW
   -D TELEM_BME280_ADDRESS=0x77
   -D DISPLAY_CLASS=GxEPDDisplay
+  -D EINK_DISPLAY_MODEL=GxEPD2_154_D67
+  -D EINK_SCALE_X=1.5625f
+  -D EINK_SCALE_Y=1.5625f
+  -D EINK_X_OFFSET=0
+  -D EINK_Y_OFFSET=10
+  -D EINK_SCREENOFF_BLANK
+  -D UI_RECENT_LIST_SIZE=9
+  -D UI_MSG_PREVIEW_SIZE=165
+  -D EINK_MAX_PARTIAL_REFRESH=60
+  -D AUTO_OFF_MILLIS=900000
   -D BACKLIGHT_BTN=PIN_BUTTON2
-  -D AUTO_OFF_MILLIS=0
 build_src_filter = ${nrf52_base.build_src_filter}
   +<helpers/*.cpp>
   +<TechoBoard.cpp>
@@ -91,7 +100,6 @@ build_flags =
   -D BLE_PIN_CODE=123456
 ;  -D BLE_DEBUG_LOGGING=1
   -D OFFLINE_QUEUE_SIZE=256
-  -D UI_RECENT_LIST_SIZE=9
   -D UI_SENSORS_PAGE=1
   -D UI_GPS_PAGE=1
 ;  -D MESH_PACKET_LOGGING=1
@@ -116,7 +124,6 @@ build_flags =
   -D MAX_CONTACTS=350
   -D MAX_GROUP_CHANNELS=40
   -D OFFLINE_QUEUE_SIZE=256
-  -D UI_RECENT_LIST_SIZE=9
   -D UI_SENSORS_PAGE=1
   -D AUTO_SHUTDOWN_MILLIVOLTS=3300
   -D QSPIFLASH=1
diff --git a/variants/lilygo_techo/target.cpp b/variants/lilygo_techo/target.cpp
index 278fc76da..12b40d7ee 100644
--- a/variants/lilygo_techo/target.cpp
+++ b/variants/lilygo_techo/target.cpp
@@ -23,6 +23,7 @@ EnvironmentSensorManager sensors = EnvironmentSensorManager();
 #ifdef DISPLAY_CLASS
   DISPLAY_CLASS display;
   MomentaryButton user_btn(PIN_USER_BTN, 1000, true);
+  MomentaryButton backlight_btn(BACKLIGHT_BTN, 1000, true);
 #endif
 
 bool radio_init() {
diff --git a/variants/lilygo_techo/target.h b/variants/lilygo_techo/target.h
index 2b8a1783f..a1668f031 100644
--- a/variants/lilygo_techo/target.h
+++ b/variants/lilygo_techo/target.h
@@ -22,6 +22,7 @@ extern EnvironmentSensorManager sensors;
 #ifdef DISPLAY_CLASS
   extern DISPLAY_CLASS display;
   extern MomentaryButton user_btn;
+  extern MomentaryButton backlight_btn;
 #endif
 
 bool radio_init();
diff --git a/variants/lilygo_techo/variant.h b/variants/lilygo_techo/variant.h
index 1de62d91a..d11aac58c 100644
--- a/variants/lilygo_techo/variant.h
+++ b/variants/lilygo_techo/variant.h
@@ -131,6 +131,12 @@ extern const int SCK;
 #define DISP_BUSY               (3)
 #define DISP_BACKLIGHT          (43)
 
+// used by GxEPDDisplay when EINK_DISPLAY_MODEL is set
+#define PIN_DISPLAY_CS          DISP_CS
+#define PIN_DISPLAY_DC          DISP_DC
+#define PIN_DISPLAY_RST         DISP_RST
+#define PIN_DISPLAY_BUSY        DISP_BUSY
+
 ////////////////////////////////////////////////////////////////////////////////
 // GPS
 
diff --git a/variants/meshtracker_x1/MeshTrackerX1Board.cpp b/variants/meshtracker_x1/MeshTrackerX1Board.cpp
index 56e537a23..94c20a63c 100644
--- a/variants/meshtracker_x1/MeshTrackerX1Board.cpp
+++ b/variants/meshtracker_x1/MeshTrackerX1Board.cpp
@@ -5,7 +5,6 @@
 
 void MeshTrackerX1Board::begin() {
   NRF52BoardDCDC::begin();
-  btn_prev_state = LOW;   // button is active HIGH
 
 #ifdef BUTTON_PIN
   pinMode(BATTERY_PIN, INPUT);
diff --git a/variants/meshtracker_x1/MeshTrackerX1Board.h b/variants/meshtracker_x1/MeshTrackerX1Board.h
index 51f022e0b..d332244f5 100644
--- a/variants/meshtracker_x1/MeshTrackerX1Board.h
+++ b/variants/meshtracker_x1/MeshTrackerX1Board.h
@@ -5,9 +5,6 @@
 #include <helpers/NRF52Board.h>
 
 class MeshTrackerX1Board : public NRF52BoardDCDC {
-protected:
-  uint8_t btn_prev_state;
-
 public:
   MeshTrackerX1Board() : NRF52Board("X1_OTA") {}
   void begin();
@@ -35,17 +32,6 @@ public:
     return "Seeed SenseCAP MeshTracker X1";
   }
 
-  int buttonStateChanged() {
-  #ifdef BUTTON_PIN
-    uint8_t v = digitalRead(BUTTON_PIN);
-    if (v != btn_prev_state) {
-      btn_prev_state = v;
-      return (v == USER_BTN_PRESSED) ? 1 : -1;
-    }
-  #endif
-    return 0;
-  }
-
   void powerOff() override {
     #ifdef HAS_GPS
         digitalWrite(GPS_VRTC_EN, LOW);
diff --git a/variants/promicro/PromicroBoard.cpp b/variants/promicro/PromicroBoard.cpp
index 7011521b8..aba808786 100644
--- a/variants/promicro/PromicroBoard.cpp
+++ b/variants/promicro/PromicroBoard.cpp
@@ -5,7 +5,6 @@
 
 void PromicroBoard::begin() {    
     NRF52Board::begin();
-    btn_prev_state = HIGH;
   
     pinMode(PIN_VBAT_READ, INPUT);
 
diff --git a/variants/promicro/PromicroBoard.h b/variants/promicro/PromicroBoard.h
index ee16c9654..605b03652 100644
--- a/variants/promicro/PromicroBoard.h
+++ b/variants/promicro/PromicroBoard.h
@@ -9,7 +9,6 @@
 
 class PromicroBoard : public NRF52BoardDCDC {
 protected:
-  uint8_t btn_prev_state;
   float adc_mult = ADC_MULTIPLIER;
 
 public:
@@ -48,15 +47,4 @@ public:
   const char* getManufacturerName() const override {
     return "ProMicro DIY";
   }
-
-  int buttonStateChanged() {
-    #ifdef BUTTON_PIN
-      uint8_t v = digitalRead(BUTTON_PIN);
-      if (v != btn_prev_state) {
-        btn_prev_state = v;
-        return (v == LOW) ? 1 : -1;
-      }
-    #endif
-      return 0;
-  }
 };
diff --git a/variants/rak4631/platformio.ini b/variants/rak4631/platformio.ini
index d2781d9fa..4c13b0d74 100644
--- a/variants/rak4631/platformio.ini
+++ b/variants/rak4631/platformio.ini
@@ -28,11 +28,14 @@ build_src_filter = ${nrf52_base.build_src_filter}
   +<../variants/rak4631>
   +<helpers/sensors>
   +<helpers/ui/SSD1306Display.cpp>
+  +<helpers/ui/SH1106Display.cpp>
+  +<helpers/ui/AutoDetectDisplay.cpp>
   +<helpers/ui/MomentaryButton.cpp>
 lib_deps =
   ${nrf52_base.lib_deps}
   ${sensor_base.lib_deps}
   adafruit/Adafruit SSD1306 @ ^2.5.13
+  adafruit/Adafruit SH110X @ ^2.1.13
   sparkfun/SparkFun u-blox GNSS Arduino Library@^2.2.27
   boschsensortec/BSEC Software Library @ ^1.8.1492
 
@@ -40,7 +43,7 @@ lib_deps =
 extends = rak4631
 build_flags =
   ${rak4631.build_flags}
-  -D DISPLAY_CLASS=SSD1306Display
+  -D DISPLAY_CLASS=AutoDetectDisplay
   -D ADVERT_NAME='"RAK4631 Repeater"'
   -D ADVERT_LAT=0.0
   -D ADVERT_LON=0.0
@@ -56,7 +59,7 @@ build_src_filter = ${rak4631.build_src_filter}
 extends = rak4631
 build_flags =
   ${rak4631.build_flags}
-  -D DISPLAY_CLASS=SSD1306Display
+  -D DISPLAY_CLASS=AutoDetectDisplay
   -D ADVERT_NAME='"RAK4631 Repeater"'
   -D ADVERT_LAT=0.0
   -D ADVERT_LON=0.0
@@ -75,7 +78,7 @@ lib_deps =
 extends = rak4631
 build_flags =
   ${rak4631.build_flags}
-  -D DISPLAY_CLASS=SSD1306Display
+  -D DISPLAY_CLASS=AutoDetectDisplay
   -D ADVERT_NAME='"RS232 Bridge"'
   -D ADVERT_LAT=0.0
   -D ADVERT_LON=0.0
@@ -98,7 +101,7 @@ build_src_filter = ${rak4631.build_src_filter}
 extends = rak4631
 build_flags =
   ${rak4631.build_flags}
-  -D DISPLAY_CLASS=SSD1306Display
+  -D DISPLAY_CLASS=AutoDetectDisplay
   -D ADVERT_NAME='"RS232 Bridge"'
   -D ADVERT_LAT=0.0
   -D ADVERT_LON=0.0
@@ -121,7 +124,7 @@ build_src_filter = ${rak4631.build_src_filter}
 extends = rak4631
 build_flags =
   ${rak4631.build_flags}
-  -D DISPLAY_CLASS=SSD1306Display
+  -D DISPLAY_CLASS=AutoDetectDisplay
   -D ADVERT_NAME='"Test Room"'
   -D ADVERT_LAT=0.0
   -D ADVERT_LON=0.0
@@ -137,7 +140,7 @@ build_src_filter = ${rak4631.build_src_filter}
 extends = rak4631
 build_flags =
   ${rak4631.build_flags}
-  -D DISPLAY_CLASS=SSD1306Display
+  -D DISPLAY_CLASS=AutoDetectDisplay
   -D ADVERT_NAME='"RAK4631 Room Server"'
   -D ADVERT_LAT=0.0
   -D ADVERT_LON=0.0
@@ -161,7 +164,7 @@ build_flags =
   -I examples/companion_radio/ui-new
   -D PIN_USER_BTN=9
   -D PIN_USER_BTN_ANA=31
-  -D DISPLAY_CLASS=SSD1306Display
+  -D DISPLAY_CLASS=AutoDetectDisplay
   -D MAX_CONTACTS=350
   -D MAX_GROUP_CHANNELS=40
   -D ENABLE_USB_INTERFACE
@@ -186,7 +189,7 @@ build_flags =
   -I examples/companion_radio/ui-new
   -D PIN_USER_BTN=9
   -D PIN_USER_BTN_ANA=31
-  -D DISPLAY_CLASS=SSD1306Display
+  -D DISPLAY_CLASS=AutoDetectDisplay
   -D MAX_CONTACTS=350
   -D MAX_GROUP_CHANNELS=40
   -D ETHERNET_ENABLED=1
@@ -215,7 +218,7 @@ build_flags =
   -I examples/companion_radio/ui-new
   -D PIN_USER_BTN=9
   -D PIN_USER_BTN_ANA=31
-  -D DISPLAY_CLASS=SSD1306Display
+  -D DISPLAY_CLASS=AutoDetectDisplay
   -D MAX_CONTACTS=350
   -D MAX_GROUP_CHANNELS=40
   -D BLE_PIN_CODE=123456
@@ -251,7 +254,7 @@ lib_deps =
 extends = rak4631
 build_flags =
   ${rak4631.build_flags}
-  -D DISPLAY_CLASS=SSD1306Display
+  -D DISPLAY_CLASS=AutoDetectDisplay
   -D ADVERT_NAME='"RAK4631 Sensor"'
   -D ADVERT_LAT=0.0
   -D ADVERT_LON=0.0
diff --git a/variants/rak4631/target.h b/variants/rak4631/target.h
index 1529f9042..c04cd4e48 100644
--- a/variants/rak4631/target.h
+++ b/variants/rak4631/target.h
@@ -9,7 +9,7 @@
 #include <helpers/sensors/EnvironmentSensorManager.h>
 
 #ifdef DISPLAY_CLASS
-  #include <helpers/ui/SSD1306Display.h>
+  #include <helpers/ui/AutoDetectDisplay.h>
   extern DISPLAY_CLASS display;
   #include <helpers/ui/MomentaryButton.h>
   extern MomentaryButton user_btn;
diff --git a/variants/t1000-e/T1000eBoard.cpp b/variants/t1000-e/T1000eBoard.cpp
index 0d390f798..1d3ce423c 100644
--- a/variants/t1000-e/T1000eBoard.cpp
+++ b/variants/t1000-e/T1000eBoard.cpp
@@ -5,7 +5,6 @@
 
 void T1000eBoard::begin() {
   NRF52BoardDCDC::begin();
-  btn_prev_state = HIGH;
 
 #ifdef BUTTON_PIN
   pinMode(BATTERY_PIN, INPUT);
diff --git a/variants/t1000-e/T1000eBoard.h b/variants/t1000-e/T1000eBoard.h
index ba8bf0c1d..653bea617 100644
--- a/variants/t1000-e/T1000eBoard.h
+++ b/variants/t1000-e/T1000eBoard.h
@@ -5,9 +5,6 @@
 #include <helpers/NRF52Board.h>
 
 class T1000eBoard : public NRF52BoardDCDC {
-protected:
-  uint8_t btn_prev_state;
-
 public:
   T1000eBoard() : NRF52Board("T1000E_OTA") {}
   void begin();
@@ -38,17 +35,6 @@ public:
     return "Seeed Tracker T1000-E";
   }
 
-  int buttonStateChanged() {
-  #ifdef BUTTON_PIN
-    uint8_t v = digitalRead(BUTTON_PIN);
-    if (v != btn_prev_state) {
-      btn_prev_state = v;
-      return (v == USER_BTN_PRESSED) ? 1 : -1;
-    }
-  #endif
-    return 0;
-  }
-
   void powerOff() override {
     #ifdef HAS_GPS
         digitalWrite(GPS_VRTC_EN, LOW);
diff --git a/variants/thinknode_m1/platformio.ini b/variants/thinknode_m1/platformio.ini
index 89c48403b..7c620e2ed 100644
--- a/variants/thinknode_m1/platformio.ini
+++ b/variants/thinknode_m1/platformio.ini
@@ -24,6 +24,18 @@ build_flags = ${nrf52_base.build_flags}
   -D SX126X_RX_BOOSTED_GAIN=1
   -D LORA_TX_POWER=22
   -D P_LORA_TX_LED=13
+  -D UI_RECENT_LIST_SIZE=9
+  -D UI_MSG_PREVIEW_SIZE=165
+  -D EINK_MAX_PARTIAL_REFRESH=60
+  -D EINK_DISPLAY_MODEL=GxEPD2_154_D67
+  -D EINK_SCALE_X=1.5625f
+  -D EINK_SCALE_Y=1.5625f
+  -D EINK_X_OFFSET=0
+  -D EINK_Y_OFFSET=10
+  -D BACKLIGHT_BTN=PIN_BUTTON2
+  -D AUTO_OFF_MILLIS=900000
+  -D UI_NO_HIBERNATE
+  -D DISABLE_DIAGNOSTIC_OUTPUT
 build_src_filter = ${nrf52_base.build_src_filter}
   +<helpers/*.cpp>
   +<ThinkNodeM1Board.cpp>
diff --git a/variants/thinknode_m1/target.cpp b/variants/thinknode_m1/target.cpp
index 69306fc0e..c430cee00 100644
--- a/variants/thinknode_m1/target.cpp
+++ b/variants/thinknode_m1/target.cpp
@@ -17,6 +17,7 @@ ThinkNodeM1SensorManager sensors = ThinkNodeM1SensorManager(nmea);
 #ifdef DISPLAY_CLASS
   DISPLAY_CLASS display;
   MomentaryButton user_btn(PIN_USER_BTN, 1000, true);
+  MomentaryButton backlight_btn(BACKLIGHT_BTN, 1000, true);
 #endif
 
 bool radio_init() {
diff --git a/variants/thinknode_m1/target.h b/variants/thinknode_m1/target.h
index ec1297bef..d2d6aed1d 100644
--- a/variants/thinknode_m1/target.h
+++ b/variants/thinknode_m1/target.h
@@ -40,6 +40,7 @@ extern ThinkNodeM1SensorManager sensors;
 #ifdef DISPLAY_CLASS
   extern DISPLAY_CLASS display;
   extern MomentaryButton user_btn;
+  extern MomentaryButton backlight_btn;
 #endif
 
 bool radio_init();
diff --git a/variants/thinknode_m1/variant.h b/variants/thinknode_m1/variant.h
index f7f52a6a5..aecf197e6 100644
--- a/variants/thinknode_m1/variant.h
+++ b/variants/thinknode_m1/variant.h
@@ -81,7 +81,7 @@
 #define BUTTON_PIN              PIN_BUTTON1
 #define PIN_USER_BTN            BUTTON_PIN
 
-#define PIN_BUTTON2             (11)
+#define PIN_BUTTON2             (39)
 #define BUTTON_PIN2             PIN_BUTTON2
 
 #define EXTERNAL_FLASH_DEVICES MX25R1635F
@@ -131,6 +131,11 @@ extern const int SCK;
 #define DISP_BUSY               (3)
 #define DISP_BACKLIGHT          (43)
 
+#define PIN_DISPLAY_CS DISP_CS
+#define PIN_DISPLAY_DC DISP_DC
+#define PIN_DISPLAY_RST DISP_RST
+#define PIN_DISPLAY_BUSY DISP_BUSY
+
 ////////////////////////////////////////////////////////////////////////////////
 // GPS
 
diff --git a/variants/thinknode_m3/ThinkNodeM3Board.cpp b/variants/thinknode_m3/ThinkNodeM3Board.cpp
index ac513ade5..518d15bda 100644
--- a/variants/thinknode_m3/ThinkNodeM3Board.cpp
+++ b/variants/thinknode_m3/ThinkNodeM3Board.cpp
@@ -6,7 +6,6 @@
 
 void ThinkNodeM3Board::begin() {
   NRF52Board::begin();
-  btn_prev_state = HIGH;
 
   Wire.begin();
 
diff --git a/variants/thinknode_m3/ThinkNodeM3Board.h b/variants/thinknode_m3/ThinkNodeM3Board.h
index 9e8f49894..bbd69d264 100644
--- a/variants/thinknode_m3/ThinkNodeM3Board.h
+++ b/variants/thinknode_m3/ThinkNodeM3Board.h
@@ -11,7 +11,6 @@ protected:
 #if NRF52_POWER_MANAGEMENT
   void initiateShutdown(uint8_t reason) override;
 #endif
-  uint8_t btn_prev_state;
 
 public:
   ThinkNodeM3Board() : NRF52Board("THINKNODE_M3_OTA") {}
@@ -31,17 +30,6 @@ public:
     return "Elecrow ThinkNode M3";
   }
 
-  int buttonStateChanged() {
-  #ifdef BUTTON_PIN
-    uint8_t v = digitalRead(BUTTON_PIN);
-    if (v != btn_prev_state) {
-      btn_prev_state = v;
-      return (v == LOW) ? 1 : -1;
-    }
-  #endif
-    return 0;
-  }
-
   void powerOff() override {
     // turn off all leds, sd_power_system_off will not do this for us
     digitalWrite(PIN_LED_BLUE, !LED_STATE_ON);
diff --git a/variants/thinknode_m4/ThinkNodeM4Board.cpp b/variants/thinknode_m4/ThinkNodeM4Board.cpp
index 4a144a3a4..281983ae3 100644
--- a/variants/thinknode_m4/ThinkNodeM4Board.cpp
+++ b/variants/thinknode_m4/ThinkNodeM4Board.cpp
@@ -6,7 +6,6 @@
 
 void ThinkNodeM4Board::begin() {
   NRF52Board::begin();
-  btn_prev_state = HIGH;
 
   Wire.begin();
   battery_serial->begin(4800);
diff --git a/variants/thinknode_m4/ThinkNodeM4Board.h b/variants/thinknode_m4/ThinkNodeM4Board.h
index c2cae54b6..63de1ff27 100644
--- a/variants/thinknode_m4/ThinkNodeM4Board.h
+++ b/variants/thinknode_m4/ThinkNodeM4Board.h
@@ -9,7 +9,6 @@ protected:
 #if NRF52_POWER_MANAGEMENT
   void initiateShutdown(uint8_t reason) override;
 #endif
-  uint8_t btn_prev_state;
   HardwareSerial * battery_serial;
   uint16_t bat_level_mv = 0;
   uint8_t bat_level_percent =0;
@@ -32,17 +31,6 @@ public:
     return "Elecrow ThinkNode M4";
   }
 
-  int buttonStateChanged() {
-  #ifdef BUTTON_PIN
-    uint8_t v = digitalRead(BUTTON_PIN);
-    if (v != btn_prev_state) {
-      btn_prev_state = v;
-      return (v == USER_BTN_PRESSED) ? 1 : -1;
-    }
-  #endif
-    return 0;
-  }
-
   void shutdownPeripherals() override {
     // shutdown common peripherals
     NRF52Board::shutdownPeripherals();
diff --git a/variants/thinknode_m5/platformio.ini b/variants/thinknode_m5/platformio.ini
index a3f348b33..a9761597d 100644
--- a/variants/thinknode_m5/platformio.ini
+++ b/variants/thinknode_m5/platformio.ini
@@ -26,8 +26,12 @@ build_flags = ${esp32_base.build_flags}
   -D EINK_SCALE_Y=1.5625f
   -D EINK_X_OFFSET=0
   -D EINK_Y_OFFSET=10
+  -D UI_RECENT_LIST_SIZE=9
+  -D UI_MSG_PREVIEW_SIZE=165
+  -D EINK_MAX_PARTIAL_REFRESH=60
   -D BACKLIGHT_BTN=PIN_BUTTON2
-  -D AUTO_OFF_MILLIS=0
+  -D AUTO_OFF_MILLIS=900000
+  -D UI_NO_HIBERNATE
   -D DISABLE_DIAGNOSTIC_OUTPUT
   -D SX126X_DIO2_AS_RF_SWITCH=true
   -D SX126X_DIO3_TCXO_VOLTAGE=3.3
@@ -150,7 +154,6 @@ build_flags =
   -D MAX_GROUP_CHANNELS=40
   -D BLE_PIN_CODE=123456
   -D OFFLINE_QUEUE_SIZE=256
-  -D UI_RECENT_LIST_SIZE=9
 ;  -D BLE_DEBUG_LOGGING=1
 ;  -D MESH_PACKET_LOGGING=1
 ;  -D GPS_NMEA_DEBUG
@@ -174,12 +177,14 @@ build_flags =
   -D MAX_GROUP_CHANNELS=40
   -D OFFLINE_QUEUE_SIZE=256
   -D ENABLE_USB_INTERFACE
+  -D ENABLE_WIFI_INTERFACE
 build_src_filter = ${ThinkNode_M5.build_src_filter}
   +<helpers/esp32/*.cpp>
   +<helpers/ui/MomentaryButton.cpp>
   +<../examples/companion_radio/*.cpp>
   +<../examples/companion_radio/ui-new/*.cpp>
   +<helpers/ui/buzzer.cpp>
+  +<helpers/wifi/*.cpp>
 lib_deps =
   ${ThinkNode_M5.lib_deps}
   densaugeo/base64 @ ~1.4.0
diff --git a/variants/thinknode_m5/target.cpp b/variants/thinknode_m5/target.cpp
index be534f67d..ec524df74 100644
--- a/variants/thinknode_m5/target.cpp
+++ b/variants/thinknode_m5/target.cpp
@@ -26,6 +26,7 @@ EnvironmentSensorManager sensors = EnvironmentSensorManager();
 #ifdef DISPLAY_CLASS
   DISPLAY_CLASS display;
   MomentaryButton user_btn(PIN_USER_BTN, 1000, true);
+  MomentaryButton backlight_btn(BACKLIGHT_BTN, 1000, true);
 #endif
 
 bool radio_init() {
diff --git a/variants/thinknode_m5/target.h b/variants/thinknode_m5/target.h
index a613e3909..7cce1edbf 100644
--- a/variants/thinknode_m5/target.h
+++ b/variants/thinknode_m5/target.h
@@ -24,6 +24,7 @@ extern PCA9557 expander;
 #ifdef DISPLAY_CLASS
   extern DISPLAY_CLASS display;
   extern MomentaryButton user_btn;
+  extern MomentaryButton backlight_btn;
 #endif
 
 bool radio_init();
diff --git a/variants/thinknode_m8/platformio.ini b/variants/thinknode_m8/platformio.ini
index db19e4466..5282f280f 100644
--- a/variants/thinknode_m8/platformio.ini
+++ b/variants/thinknode_m8/platformio.ini
@@ -18,12 +18,16 @@ build_flags = ${nrf52_base.build_flags}
   -D P_LORA_SCLK=19
   -D P_LORA_MISO=22
   -D P_LORA_MOSI=20
-  -D UI_SHOW_CLOCK=1
+  -D DISPLAY_ROTATION=4
   -D UI_HAS_ROTARY_INPUT=1
   -D UI_HAS_NAV_INPUT=1
   -D UI_RECENT_LIST_SIZE=9
   -D UI_MSG_PREVIEW_SIZE=165
   -D EINK_MAX_PARTIAL_REFRESH=60
+  -D AUTO_OFF_MILLIS=900000
+  -D BACKLIGHT_BTN=PIN_BUTTON2
+  -D UI_SHOW_CLOCK=1
+  -D EINK_SCREENOFF_BLANK
   -D EINK_DISPLAY_MODEL=GxEPD2_154_D67
 ;  -D EINK_DISPLAY_MODEL=GxEPD2_154_GDEY0154D67
 ;  -D EINK_DISPLAY_MODEL=GxEPD2_150_BN
@@ -40,6 +44,7 @@ build_flags = ${nrf52_base.build_flags}
   -D LORA_TX_POWER=22
 build_src_filter = ${nrf52_base.build_src_filter}
   +<helpers/*.cpp>
+  +<helpers/sensors>
   +<ThinkNodeM8Board.cpp>
   +<../variants/thinknode_m8>
 lib_deps =
@@ -92,10 +97,7 @@ build_flags =
   -D MAX_GROUP_CHANNELS=40
   -D BLE_PIN_CODE=123456
 #  -D BLE_DEBUG_LOGGING=1
-  -D DISPLAY_ROTATION=4
   -D DISPLAY_CLASS=GxEPDDisplay
-  -D BACKLIGHT_BTN=PIN_BUTTON2
-  -D AUTO_OFF_MILLIS=0
   -D OFFLINE_QUEUE_SIZE=256
   -D PIN_BUZZER=33
   -D AUTO_SHUTDOWN_MILLIVOLTS=3300
@@ -110,7 +112,6 @@ build_src_filter = ${ThinkNode_M8.build_src_filter}
   +<helpers/ui/buzzer.cpp>
   +<helpers/ui/MomentaryButton.cpp>
   +<helpers/ui/RotaryInputGPIO.cpp>
-  +<helpers/sensors/EnvironmentSensorManager.cpp>
   +<../examples/companion_radio/*.cpp>
   +<../examples/companion_radio/ui-new/*.cpp>
 lib_deps =
@@ -133,8 +134,6 @@ build_flags =
   -D DISPLAY_ROTATION=4
   -D QSPIFLASH=1
   -D DISPLAY_CLASS=GxEPDDisplay
-  -D BACKLIGHT_BTN=PIN_BUTTON2
-  -D AUTO_OFF_MILLIS=0
   -D OFFLINE_QUEUE_SIZE=256
   -D PIN_BUZZER=6
   -D AUTO_SHUTDOWN_MILLIVOLTS=3300
@@ -144,7 +143,6 @@ build_src_filter = ${ThinkNode_M8.build_src_filter}
   +<helpers/ui/buzzer.cpp>
   +<helpers/ui/MomentaryButton.cpp>
   +<helpers/ui/RotaryInputGPIO.cpp>
-  +<helpers/sensors/EnvironmentSensorManager.cpp>
   +<../examples/companion_radio/*.cpp>
   +<../examples/companion_radio/ui-new/*.cpp>
 lib_deps =
diff --git a/variants/thinknode_m8/target.cpp b/variants/thinknode_m8/target.cpp
index ac4ac100e..69f3cc526 100644
--- a/variants/thinknode_m8/target.cpp
+++ b/variants/thinknode_m8/target.cpp
@@ -23,6 +23,7 @@ EnvironmentSensorManager sensors = EnvironmentSensorManager();
   DISPLAY_CLASS display;
   MomentaryButton user_btn(PIN_USER_BTN, 1000, true);
   RotaryInputGPIO rotary_input(PIN_BUTTON1_A, PIN_BUTTON1_B);
+  MomentaryButton backlight_btn(BACKLIGHT_BTN, 1000, true);
 #endif
 
 bool radio_init() {
diff --git a/variants/thinknode_m8/target.h b/variants/thinknode_m8/target.h
index c3402a01a..399285065 100644
--- a/variants/thinknode_m8/target.h
+++ b/variants/thinknode_m8/target.h
@@ -23,6 +23,7 @@ extern EnvironmentSensorManager sensors;
 #ifdef DISPLAY_CLASS
   extern DISPLAY_CLASS display;
   extern MomentaryButton user_btn;
+  extern MomentaryButton backlight_btn;
   extern RotaryInputGPIO rotary_input;
 #endif