diff --git a/Marlin/src/inc/Conditionals-2-LCD.h b/Marlin/src/inc/Conditionals-2-LCD.h
index 6aa8b25e99..d8cc8ac3c8 100644
--- a/Marlin/src/inc/Conditionals-2-LCD.h
+++ b/Marlin/src/inc/Conditionals-2-LCD.h
@@ -552,6 +552,38 @@
   #define HAS_WIRED_LCD 1
 #endif
 
+
+// Compile-time diagnostic warnings for MightyBoard builds
+#if ENABLED(MIGHTYBOARD_LCD)
+  #warning "MightyBoard build: MIGHTYBOARD_LCD is ENABLED"
+  #if ENABLED(IS_ULTIPANEL)
+    #warning "MightyBoard build: IS_ULTIPANEL is defined"
+  #else
+    #warning "MightyBoard build: IS_ULTIPANEL is NOT defined"
+  #endif
+  #if ENABLED(HAS_WIRED_LCD)
+    #warning "MightyBoard build: HAS_WIRED_LCD is defined"
+  #else
+    #warning "MightyBoard build: HAS_WIRED_LCD is NOT defined"
+  #endif
+  #if ENABLED(HAS_MARLINUI_HD44780)
+    #warning "MightyBoard build: HAS_MARLINUI_HD44780 is defined"
+  #else
+    #warning "MightyBoard build: HAS_MARLINUI_HD44780 is NOT defined"
+  #endif
+  #if ENABLED(HAS_MARLINUI_MENU)
+    #warning "MightyBoard build: HAS_MARLINUI_MENU is defined"
+  #else
+    #warning "MightyBoard build: HAS_MARLINUI_MENU is NOT defined"
+  #endif
+  #if ENABLED(HAS_SHIFT_ENCODER)
+    #warning "MightyBoard build: HAS_SHIFT_ENCODER is defined"
+  #else
+    #warning "MightyBoard build: HAS_SHIFT_ENCODER is NOT defined"
+  #endif
+#endif
+
+
 #if ANY(IS_ULTIPANEL, REPRAPWORLD_KEYPAD)
   #define IS_NEWPANEL 1
 #endif
diff --git a/Marlin/src/lcd/buttons.h b/Marlin/src/lcd/buttons.h
index 2bd5fd7b35..8bf76b784d 100644
--- a/Marlin/src/lcd/buttons.h
+++ b/Marlin/src/lcd/buttons.h
@@ -28,6 +28,7 @@
 #endif
 #if (HAS_MARLINUI_ENCODER || ANY_BUTTON(ENC, BACK, UP, DOWN, LEFT, RIGHT)) && DISABLED(TOUCH_UI_FTDI_EVE)
   #define HAS_DIGITAL_BUTTONS 1
+  #warning "HAS_DIGITAL_BUTTONS enabled"
 #endif
 #if !HAS_ADC_BUTTONS && (IS_RRW_KEYPAD || (HAS_WIRED_LCD && !IS_NEWPANEL))
   #define HAS_SHIFT_ENCODER 1
diff --git a/Marlin/src/lcd/marlinui.cpp b/Marlin/src/lcd/marlinui.cpp
index 27613756b5..9fa602e07f 100644
--- a/Marlin/src/lcd/marlinui.cpp
+++ b/Marlin/src/lcd/marlinui.cpp
@@ -313,6 +313,39 @@ void MarlinUI::init() {
       SET_INPUT(BTN_RIGHT);
     #endif
   #endif
+
+  // Compile-time warnings to confirm whether this directional-button init block
+  // is compiled for the current board. These will appear in the compiler output
+  // only when ANY_BUTTON(UP, DOWN, LFT, RT) evaluates true for the current build.
+  #if ANY_BUTTON(UP, DOWN, LFT, RT)
+    #warning "Marlin: Compiling directional button init (UP/DOWN/LEFT/RIGHT)"
+  #endif
+
+  // Optional runtime trace for MightyBoard UI/button flow.
+  // Enable by uncommenting `#define MIGHTYBOARD_RUNTIME_DEBUG` in the board pins file.
+  #if ENABLED(MIGHTYBOARD_RUNTIME_DEBUG)
+    SERIAL_ECHOLN("MarlinUI::init() - MIGHTYBOARD_RUNTIME_DEBUG active");
+    #if ENABLED(MIGHTYBOARD_BUTTON_PULLUPS)
+      SERIAL_ECHOLN("MIGHTYBOARD_BUTTON_PULLUPS: ENABLED");
+    #else
+      SERIAL_ECHOLN("MIGHTYBOARD_BUTTON_PULLUPS: DISABLED");
+    #endif
+    SERIAL_ECHO_MSG("LCD dimensions: ", LCD_WIDTH, " x ", LCD_HEIGHT);
+    SERIAL_ECHOLN("");
+
+    // Report encoder/click compile-time presence and pin numbers (if defined)
+    #if BUTTON_EXISTS(ENC)
+      SERIAL_ECHOLN("BUTTON_EXISTS(ENC): defined");
+      SERIAL_ECHO_MSG("BTN_ENC pin: ", BTN_ENC);
+      SERIAL_ECHOLN("");
+    #else
+      SERIAL_ECHOLN("BUTTON_EXISTS(ENC): NOT defined");
+    #endif
+
+    #ifdef BTN_CLICK
+      SERIAL_ECHO_MSG("BTN_CLICK pin: ", BTN_CLICK);
+      SERIAL_ECHOLN("");
+    #endif
   #endif
 
   #if HAS_SHIFT_ENCODER
@@ -1347,6 +1380,18 @@ void MarlinUI::init() {
     void MarlinUI::update_buttons() {
       const millis_t now = millis();
 
+        // #if ENABLED(MIGHTYBOARD_RUNTIME_DEBUG)
+        //   // Debug: print raw pin reads for encoder/click to diagnose BTN_ENC alias
+        //   #if BUTTON_EXISTS(ENC)
+        //     SERIAL_ECHO_MSG("DBG: READ(BTN_ENC) = ", READ(BTN_ENC));
+        //     SERIAL_ECHOLN("");
+        //   #endif
+        //   #ifdef BTN_CLICK
+        //     SERIAL_ECHO_MSG("DBG: READ(BTN_CLICK) = ", READ(BTN_CLICK));
+        //     SERIAL_ECHOLN("");
+        //   #endif
+        // #endif
+
       #if HAS_MARLINUI_ENCODER
 
         const int8_t delta = get_encoder_delta(now);
@@ -1379,18 +1424,34 @@ void MarlinUI::init() {
           if (BUTTON_PRESSED(UP)) {
             encoderDiff = pulses * (ENCODER_STEPS_PER_MENU_ITEM);
             next_button_update_ms = now + 300;
+            // #if ENABLED(MIGHTYBOARD_RUNTIME_DEBUG)
+            //   SERIAL_ECHO_MSG("update_buttons(): UP -> encoderDiff=", encoderDiff);
+            //   SERIAL_ECHOLN("");
+            // #endif
           }
           else if (BUTTON_PRESSED(DOWN)) {
             encoderDiff = pulses * -(ENCODER_STEPS_PER_MENU_ITEM);
             next_button_update_ms = now + 300;
+            // #if ENABLED(MIGHTYBOARD_RUNTIME_DEBUG)
+            //   SERIAL_ECHO_MSG("update_buttons(): DOWN -> encoderDiff=", encoderDiff);
+            //   SERIAL_ECHOLN("");
+            // #endif
           }
           else if (BUTTON_PRESSED(LEFT)) {
             encoderDiff = -pulses;
             next_button_update_ms = now + 300;
+            // #if ENABLED(MIGHTYBOARD_RUNTIME_DEBUG)
+            //   SERIAL_ECHO_MSG("update_buttons(): LEFT -> encoderDiff=", encoderDiff);
+            //   SERIAL_ECHOLN("");
+            // #endif
           }
           else if (BUTTON_PRESSED(RIGHT)) {
             encoderDiff = pulses;
             next_button_update_ms = now + 300;
+            // #if ENABLED(MIGHTYBOARD_RUNTIME_DEBUG)
+            //   SERIAL_ECHO_MSG("update_buttons(): RIGHT -> encoderDiff=", encoderDiff);
+            //   SERIAL_ECHOLN("");
+            // #endif
           }
 
         #endif // UP || DOWN || LEFT || RIGHT