diff --git a/Marlin/Conditionals_LCD.h b/Marlin/Conditionals_LCD.h
index 3c39512a93..b33499e6bf 100644
--- a/Marlin/Conditionals_LCD.h
+++ b/Marlin/Conditionals_LCD.h
@@ -243,7 +243,7 @@
     /* Custom characters defined in the first 8 characters of the LCD */
     #define LCD_BEDTEMP_CHAR     0x00  // Print only as a char. This will have 'unexpected' results when used in a string!
     #define LCD_DEGREE_CHAR      0x01
-    #define LCD_STR_THERMOMETER "\x02" // Too many places use preprocessor string concatination to change this to a char right now.
+    #define LCD_STR_THERMOMETER "\x02" // Still used with string concatenation
     #define LCD_UPLEVEL_CHAR     0x03
     #define LCD_REFRESH_CHAR     0x04
     #define LCD_STR_FOLDER      "\x05"
diff --git a/Marlin/Configuration_adv.h b/Marlin/Configuration_adv.h
index 2665bddb6f..0db274d13b 100644
--- a/Marlin/Configuration_adv.h
+++ b/Marlin/Configuration_adv.h
@@ -225,13 +225,11 @@
  */
 //#define CASE_LIGHT_ENABLE
 #if ENABLED(CASE_LIGHT_ENABLE)
-  #define CASE_LIGHT_PIN 4          // can be defined here or in the pins_XXX.h file for your board
-                                    //  pins_XXX.h file overrides this one
-  #define INVERT_CASE_LIGHT false             // set to true if case light is ON when pin is at 0
-  #define CASE_LIGHT_DEFAULT_ON true          // set default power up state to on or off
-  #define CASE_LIGHT_DEFAULT_BRIGHTNESS 105   // set power up brightness 0-255 ( only used if on PWM
-                                              // and if CASE_LIGHT_DEFAULT is set to on
-  //#define MENU_ITEM_CASE_LIGHT              // Uncomment to have a Case Light entry in main menu
+  //#define CASE_LIGHT_PIN 4                  // Override the default pin if needed
+  #define INVERT_CASE_LIGHT false             // Set true if Case Light is ON when pin is LOW
+  #define CASE_LIGHT_DEFAULT_ON true          // Set default power-up state on
+  #define CASE_LIGHT_DEFAULT_BRIGHTNESS 105   // Set default power-up brightness (0-255, requires PWM pin)
+  //#define MENU_ITEM_CASE_LIGHT              // Add a Case Light option to the LCD main menu
 #endif
 
 //===========================================================================
diff --git a/Marlin/Marlin_main.cpp b/Marlin/Marlin_main.cpp
index 1717026b3f..c4866d89a5 100644
--- a/Marlin/Marlin_main.cpp
+++ b/Marlin/Marlin_main.cpp
@@ -458,7 +458,7 @@ volatile bool wait_for_heatup = true;
   volatile bool wait_for_user = false;
 #endif
 
-const char axis_codes[XYZE] = {'X', 'Y', 'Z', 'E'};
+const char axis_codes[XYZE] = { 'X', 'Y', 'Z', 'E' };
 
 // Number of characters read in the current line of serial input
 static int serial_count = 0;
@@ -1394,7 +1394,7 @@ bool get_target_extruder_from_command(int code) {
  *
  * Callers must sync the planner position after calling this!
  */
-static void set_axis_is_at_home(AxisEnum axis) {
+static void set_axis_is_at_home(const AxisEnum axis) {
   #if ENABLED(DEBUG_LEVELING_FEATURE)
     if (DEBUGGING(LEVELING)) {
       SERIAL_ECHOPAIR(">>> set_axis_is_at_home(", axis_codes[axis]);
@@ -1496,7 +1496,7 @@ static void set_axis_is_at_home(AxisEnum axis) {
 /**
  * Some planner shorthand inline functions
  */
-inline float get_homing_bump_feedrate(AxisEnum axis) {
+inline float get_homing_bump_feedrate(const AxisEnum axis) {
   int constexpr homing_bump_divisor[] = HOMING_BUMP_DIVISOR;
   int hbd = homing_bump_divisor[axis];
   if (hbd < 1) {
@@ -1507,20 +1507,19 @@ inline float get_homing_bump_feedrate(AxisEnum axis) {
   return homing_feedrate_mm_s[axis] / hbd;
 }
 
-//
-// line_to_current_position
-// Move the planner to the current position from wherever it last moved
-// (or from wherever it has been told it is located).
-//
+/**
+ * Move the planner to the current position from wherever it last moved
+ * (or from wherever it has been told it is located).
+ */
 inline void line_to_current_position() {
   planner.buffer_line(current_position[X_AXIS], current_position[Y_AXIS], current_position[Z_AXIS], current_position[E_AXIS], feedrate_mm_s, active_extruder);
 }
 
-//
-// line_to_destination
-// Move the planner, not necessarily synced with current_position
-//
-inline void line_to_destination(float fr_mm_s) {
+/**
+ * Move the planner to the position stored in the destination array, which is
+ * used by G0/G1/G2/G3/G5 and many other functions to set a destination.
+ */
+inline void line_to_destination(const float fr_mm_s) {
   planner.buffer_line(destination[X_AXIS], destination[Y_AXIS], destination[Z_AXIS], destination[E_AXIS], fr_mm_s, active_extruder);
 }
 inline void line_to_destination() { line_to_destination(feedrate_mm_s); }
@@ -2751,7 +2750,7 @@ static void clean_up_after_endstop_or_probe_move() {
 /**
  * Home an individual linear axis
  */
-static void do_homing_move(const AxisEnum axis, float distance, float fr_mm_s=0.0) {
+static void do_homing_move(const AxisEnum axis, const float distance, const float fr_mm_s=0.0) {
 
   #if ENABLED(DEBUG_LEVELING_FEATURE)
     if (DEBUGGING(LEVELING)) {
@@ -4907,7 +4906,7 @@ void home_all_axes() { gcode_G28(true); }
         if ( NEAR(current_position[X_AXIS], xProbe - (X_PROBE_OFFSET_FROM_EXTRUDER))
           && NEAR(current_position[Y_AXIS], yProbe - (Y_PROBE_OFFSET_FROM_EXTRUDER))
         ) {
-          float simple_z = current_position[Z_AXIS] - measured_z;
+          const float simple_z = current_position[Z_AXIS] - measured_z;
           #if ENABLED(DEBUG_LEVELING_FEATURE)
             if (DEBUGGING(LEVELING)) {
               SERIAL_ECHOPAIR("Z from Probe:", simple_z);
@@ -7667,45 +7666,32 @@ void report_current_position() {
 
 #ifdef M114_DETAIL
 
-  static const char axis_char[XYZE] = {'X','Y','Z','E'};
-
-  void report_xyze(const float pos[XYZE], uint8_t n = 4, uint8_t precision = 3) {
+  void report_xyze(const float pos[XYZE], const uint8_t n = 4, const uint8_t precision = 3) {
     char str[12];
-    for(uint8_t i=0; i<n; i++) {
+    for (uint8_t i = 0; i < n; i++) {
       SERIAL_CHAR(' ');
-      SERIAL_CHAR(axis_char[i]);
+      SERIAL_CHAR(axis_codes[i]);
       SERIAL_CHAR(':');
-      SERIAL_PROTOCOL(dtostrf(pos[i],8,precision,str));
+      SERIAL_PROTOCOL(dtostrf(pos[i], 8, precision, str));
     }
     SERIAL_EOL;
   }
 
-  inline void report_xyz(const float pos[XYZ]) {
-    report_xyze(pos,3);
-  }
+  inline void report_xyz(const float pos[XYZ]) { report_xyze(pos, 3); }
 
   void report_current_position_detail() {
 
     stepper.synchronize();
 
-    SERIAL_EOL;
-    SERIAL_PROTOCOLPGM("Logical:");
+    SERIAL_PROTOCOLPGM("\nLogical:");
     report_xyze(current_position);
 
     SERIAL_PROTOCOLPGM("Raw:    ");
-    const float raw[XYZ] = {
-      RAW_X_POSITION(current_position[X_AXIS]),
-      RAW_Y_POSITION(current_position[Y_AXIS]),
-      RAW_Z_POSITION(current_position[Z_AXIS])
-    };
+    const float raw[XYZ] = { RAW_X_POSITION(current_position[X_AXIS]), RAW_Y_POSITION(current_position[Y_AXIS]), RAW_Z_POSITION(current_position[Z_AXIS]) };
     report_xyz(raw);
 
     SERIAL_PROTOCOLPGM("Leveled:");
-    float leveled[XYZ] = {
-      current_position[X_AXIS],
-      current_position[Y_AXIS],
-      current_position[Z_AXIS]
-    };
+    float leveled[XYZ] = { current_position[X_AXIS], current_position[Y_AXIS], current_position[Z_AXIS] };
     planner.apply_leveling(leveled);
     report_xyz(leveled);
 
@@ -7725,13 +7711,8 @@ void report_current_position() {
     #endif
 
     SERIAL_PROTOCOLPGM("Stepper:");
-    const float step_count[XYZE] = {
-      (float)stepper.position(X_AXIS),
-      (float)stepper.position(Y_AXIS),
-      (float)stepper.position(Z_AXIS),
-      (float)stepper.position(E_AXIS)
-    };
-    report_xyze(step_count,4,0);
+    const float step_count[XYZE] = { stepper.position(X_AXIS), stepper.position(Y_AXIS), stepper.position(Z_AXIS), stepper.position(E_AXIS) };
+    report_xyze(step_count, 4, 0);
 
     #if IS_SCARA
       const float deg[XYZ] = {
@@ -7739,17 +7720,12 @@ void report_current_position() {
         stepper.get_axis_position_degrees(B_AXIS)
       };
       SERIAL_PROTOCOLPGM("Degrees:");
-      report_xyze(deg,2);
+      report_xyze(deg, 2);
     #endif
 
     SERIAL_PROTOCOLPGM("FromStp:");
     get_cartesian_from_steppers();  // writes cartes[XYZ] (with forward kinematics)
-    const float from_steppers[XYZE] = {
-      cartes[X_AXIS],
-      cartes[Y_AXIS],
-      cartes[Z_AXIS],
-      stepper.get_axis_position_mm(E_AXIS)
-    };
+    const float from_steppers[XYZE] = { cartes[X_AXIS], cartes[Y_AXIS], cartes[Z_AXIS], stepper.get_axis_position_mm(E_AXIS) };
     report_xyze(from_steppers);
 
     const float diff[XYZE] = {
@@ -7764,12 +7740,12 @@ void report_current_position() {
 #endif // M114_DETAIL
 
 /**
- * M114: Output current position to serial port
+ * M114: Report current position to host
  */
 inline void gcode_M114() {
 
   #ifdef M114_DETAIL
-    if ( parser.seen('D') ) {
+    if (parser.seen('D')) {
       report_current_position_detail();
       return;
     }
@@ -7777,7 +7753,7 @@ inline void gcode_M114() {
 
   stepper.synchronize();
   report_current_position();
-  }
+}
 
 /**
  * M115: Capabilities string
@@ -7859,9 +7835,7 @@ inline void gcode_M115() {
 /**
  * M117: Set LCD Status Message
  */
-inline void gcode_M117() {
-  lcd_setstatus(parser.string_arg);
-}
+inline void gcode_M117() { lcd_setstatus(parser.string_arg); }
 
 /**
  * M119: Output endstop states to serial output
@@ -12749,7 +12723,7 @@ void setup() {
   #if ENABLED(ENDSTOP_INTERRUPTS_FEATURE)
     setup_endstop_interrupts();
   #endif
-  
+
   #if ENABLED(SWITCHING_EXTRUDER)
     move_extruder_servo(0);  // Initialize extruder servo
   #endif
diff --git a/Marlin/buzzer.h b/Marlin/buzzer.h
index 9441875303..530b729683 100644
--- a/Marlin/buzzer.h
+++ b/Marlin/buzzer.h
@@ -104,7 +104,7 @@ class Buzzer {
      * @param duration Duration of the tone in milliseconds
      * @param frequency Frequency of the tone in hertz
      */
-    void tone(uint16_t const &duration, uint16_t const &frequency = 0) {
+    void tone(const uint16_t &duration, const uint16_t &frequency = 0) {
       while (buffer.isFull()) {
         this->tick();
         thermalManager.manage_heater();
diff --git a/Marlin/configuration_store.cpp b/Marlin/configuration_store.cpp
index f1c1b82e2b..d9d71ce4b4 100644
--- a/Marlin/configuration_store.cpp
+++ b/Marlin/configuration_store.cpp
@@ -457,10 +457,10 @@ void MarlinSettings::postprocess() {
     #endif
 
     #if DISABLED(ULTIPANEL)
-      const int lcd_preheat_hotend_temp[2] = { PREHEAT_1_TEMP_HOTEND, PREHEAT_2_TEMP_HOTEND },
-                lcd_preheat_bed_temp[2] = { PREHEAT_1_TEMP_BED, PREHEAT_2_TEMP_BED },
-                lcd_preheat_fan_speed[2] = { PREHEAT_1_FAN_SPEED, PREHEAT_2_FAN_SPEED };
-    #endif // !ULTIPANEL
+      constexpr int lcd_preheat_hotend_temp[2] = { PREHEAT_1_TEMP_HOTEND, PREHEAT_2_TEMP_HOTEND },
+                    lcd_preheat_bed_temp[2] = { PREHEAT_1_TEMP_BED, PREHEAT_2_TEMP_BED },
+                    lcd_preheat_fan_speed[2] = { PREHEAT_1_FAN_SPEED, PREHEAT_2_FAN_SPEED };
+    #endif
 
     EEPROM_WRITE(lcd_preheat_hotend_temp);
     EEPROM_WRITE(lcd_preheat_bed_temp);
diff --git a/Marlin/temperature.cpp b/Marlin/temperature.cpp
index 40df64b67a..ea3a9a91f2 100644
--- a/Marlin/temperature.cpp
+++ b/Marlin/temperature.cpp
@@ -52,7 +52,7 @@
 #endif
 
 #if ENABLED(TEMP_SENSOR_1_AS_REDUNDANT)
-  static void* heater_ttbl_map[2] = {(void*)HEATER_0_TEMPTABLE, (void*)HEATER_1_TEMPTABLE };
+  static void* heater_ttbl_map[2] = { (void*)HEATER_0_TEMPTABLE, (void*)HEATER_1_TEMPTABLE };
   static uint8_t heater_ttbllen_map[2] = { HEATER_0_TEMPTABLE_LEN, HEATER_1_TEMPTABLE_LEN };
 #else
   static void* heater_ttbl_map[HOTENDS] = ARRAY_BY_HOTENDS((void*)HEATER_0_TEMPTABLE, (void*)HEATER_1_TEMPTABLE, (void*)HEATER_2_TEMPTABLE, (void*)HEATER_3_TEMPTABLE, (void*)HEATER_4_TEMPTABLE);
diff --git a/Marlin/ultralcd_impl_HD44780.h b/Marlin/ultralcd_impl_HD44780.h
index d1ddd3ba1b..ed7d630b47 100644
--- a/Marlin/ultralcd_impl_HD44780.h
+++ b/Marlin/ultralcd_impl_HD44780.h
@@ -193,18 +193,19 @@ extern volatile uint8_t buttons;  //an extended version of the last checked butt
   static void lcd_implementation_update_indicators();
 #endif
 
-
-static void createChar_P(char c, PROGMEM byte *ptr) {
+static void createChar_P(const char c, const byte * const ptr) {
   byte temp[8];
-  int8_t i;
-
-  for(i=0; i<8; i++)  {
+  for (uint8_t i = 0; i < 8; i++)
     temp[i] = pgm_read_byte(&ptr[i]);
-  }
   lcd.createChar(c, temp);
 }
 
-const static PROGMEM byte bedTemp[8] = {
+static void lcd_set_custom_characters(
+  #if ENABLED(LCD_PROGRESS_BAR)
+    const bool info_screen_charset = true
+  #endif
+) {
+  const static PROGMEM byte bedTemp[8] = {
     B00000,
     B11111,
     B10101,
@@ -213,9 +214,9 @@ const static PROGMEM byte bedTemp[8] = {
     B11111,
     B00000,
     B00000
-};
+  };
 
-const static PROGMEM byte degree[8] = {
+  const static PROGMEM byte degree[8] = {
     B01100,
     B10010,
     B10010,
@@ -226,7 +227,7 @@ const static PROGMEM byte degree[8] = {
     B00000
   };
 
-const static PROGMEM byte thermometer[8] = {
+  const static PROGMEM byte thermometer[8] = {
     B00100,
     B01010,
     B01010,
@@ -237,7 +238,7 @@ const static PROGMEM byte thermometer[8] = {
     B01110
   };
 
-const static PROGMEM byte uplevel[8] = {
+  const static PROGMEM byte uplevel[8] = {
     B00100,
     B01110,
     B11111,
@@ -246,9 +247,9 @@ const static PROGMEM byte uplevel[8] = {
     B00000,
     B00000,
     B00000
-};
+  };
 
-const static PROGMEM byte feedrate[8] = {
+  const static PROGMEM byte feedrate[8] = {
     B11100,
     B10000,
     B11000,
@@ -257,9 +258,9 @@ const static PROGMEM byte feedrate[8] = {
     B00110,
     B00101,
     B00000
-};
+  };
 
-const static PROGMEM byte clock[8] = {
+  const static PROGMEM byte clock[8] = {
     B00000,
     B01110,
     B10011,
@@ -268,10 +269,10 @@ const static PROGMEM byte clock[8] = {
     B01110,
     B00000,
     B00000
-};
+  };
 
-#if ENABLED(SDSUPPORT)
-  const static PROGMEM byte refresh[8] = {
+  #if ENABLED(SDSUPPORT)
+    const static PROGMEM byte refresh[8] = {
       B00000,
       B00110,
       B11001,
@@ -280,8 +281,8 @@ const static PROGMEM byte clock[8] = {
       B10011,
       B01100,
       B00000,
-  };
-  const static PROGMEM byte folder[8] = {
+    };
+    const static PROGMEM byte folder[8] = {
       B00000,
       B11100,
       B11111,
@@ -290,10 +291,10 @@ const static PROGMEM byte clock[8] = {
       B11111,
       B00000,
       B00000
-  };
+    };
 
-  #if ENABLED(LCD_PROGRESS_BAR)
-    const static PROGMEM byte progress[3][8] = { {
+    #if ENABLED(LCD_PROGRESS_BAR)
+      const static PROGMEM byte progress[3][8] = { {
         B00000,
         B10000,
         B10000,
@@ -321,14 +322,8 @@ const static PROGMEM byte clock[8] = {
         B10101,
         B00000
       } };
+    #endif
   #endif
-#endif
-
-static void lcd_set_custom_characters(
-  #if ENABLED(LCD_PROGRESS_BAR)
-    const bool info_screen_charset = true
-  #endif
-) {
 
   createChar_P(LCD_BEDTEMP_CHAR, bedTemp);
   createChar_P(LCD_DEGREE_CHAR, degree);
@@ -638,10 +633,12 @@ FORCE_INLINE void _draw_heater_status(const int8_t heater, const char prefix, co
 #if ENABLED(LCD_PROGRESS_BAR)
 
   inline void lcd_draw_progress_bar(const uint8_t percent) {
-    int tix = (int)(percent * (LCD_WIDTH) * 3) / 100,
-      cel = tix / 3, rem = tix % 3, i = LCD_WIDTH;
+    const int tix = (int)(percent * (LCD_WIDTH) * 3) / 100,
+              cel = tix / 3,
+              rem = tix % 3;
+    uint8_t i = LCD_WIDTH;
     char msg[LCD_WIDTH + 1], b = ' ';
-    msg[i] = '\0';
+    msg[LCD_WIDTH] = '\0';
     while (i--) {
       if (i == cel - 1)
         b = LCD_STR_PROGRESS[2];