diff --git a/Marlin/src/MarlinCore.cpp b/Marlin/src/MarlinCore.cpp
index be81388f38..dbfb822015 100644
--- a/Marlin/src/MarlinCore.cpp
+++ b/Marlin/src/MarlinCore.cpp
@@ -263,7 +263,7 @@
 
 PGMSTR(M112_KILL_STR, "M112 Shutdown");
 
-MarlinState marlin_state = MF_INITIALIZING;
+MarlinState marlin_state = MarlinState::MF_INITIALIZING;
 
 // For M109 and M190, this flag may be cleared (by M108) to exit the wait loop
 bool wait_for_heatup = false;
@@ -377,8 +377,8 @@ void startOrResumeJob() {
   }
 
   inline void finishSDPrinting() {
-    if (queue.enqueue_one(F("M1001"))) {  // Keep trying until it gets queued
-      marlin_state = MF_RUNNING;          // Signal to stop trying
+    if (queue.enqueue_one(F("M1001"))) {      // Keep trying until it gets queued
+      marlin_state = MarlinState::MF_RUNNING; // Signal to stop trying
       TERN_(PASSWORD_AFTER_SD_PRINT_END, password.lock_machine());
       TERN_(DGUS_LCD_UI_MKS, screen.sdPrintingFinished());
     }
@@ -773,7 +773,7 @@ void idle(const bool no_stepper_sleep/*=false*/) {
   TERN_(MAX7219_DEBUG, max7219.idle_tasks());
 
   // Return if setup() isn't completed
-  if (marlin_state == MF_INITIALIZING) goto IDLE_DONE;
+  if (marlin_state == MarlinState::MF_INITIALIZING) goto IDLE_DONE;
 
   // TODO: Still causing errors
   TERN_(TOOL_SENSOR, (void)check_tool_sensor_stats(active_extruder, true));
@@ -959,7 +959,7 @@ void stop() {
     SERIAL_ERROR_MSG(STR_ERR_STOPPED);
     LCD_MESSAGE(MSG_STOPPED);
     safe_delay(350);       // allow enough time for messages to get out before stopping
-    marlin_state = MF_STOPPED;
+    marlin_state = MarlinState::MF_STOPPED;
   }
 }
 
@@ -1646,7 +1646,7 @@ void setup() {
     SETUP_RUN(ftMotion.init());
   #endif
 
-  marlin_state = MF_RUNNING;
+  marlin_state = MarlinState::MF_RUNNING;
 
   #ifdef STARTUP_TUNE
     // Play a short startup tune before continuing.
@@ -1678,7 +1678,7 @@ void loop() {
 
     #if HAS_MEDIA
       if (card.flag.abort_sd_printing) abortSDPrinting();
-      if (marlin_state == MF_SD_COMPLETE) finishSDPrinting();
+      if (marlin_state == MarlinState::MF_SD_COMPLETE) finishSDPrinting();
     #endif
 
     queue.advance();
diff --git a/Marlin/src/MarlinCore.h b/Marlin/src/MarlinCore.h
index e9c63bb31f..9cf74de2c6 100644
--- a/Marlin/src/MarlinCore.h
+++ b/Marlin/src/MarlinCore.h
@@ -42,7 +42,7 @@ void kill(FSTR_P const lcd_error=nullptr, FSTR_P const lcd_component=nullptr, co
 void minkill(const bool steppers_off=false);
 
 // Global State of the firmware
-enum MarlinState : uint8_t {
+enum class MarlinState : uint8_t {
   MF_INITIALIZING = 0,
   MF_STOPPED,
   MF_KILLED,
@@ -53,8 +53,8 @@ enum MarlinState : uint8_t {
 };
 
 extern MarlinState marlin_state;
-inline bool IsRunning() { return marlin_state >= MF_RUNNING; }
-inline bool IsStopped() { return marlin_state == MF_STOPPED; }
+inline bool IsRunning() { return marlin_state >= MarlinState::MF_RUNNING; }
+inline bool IsStopped() { return marlin_state == MarlinState::MF_STOPPED; }
 
 bool printingIsActive();
 bool printJobOngoing();
diff --git a/Marlin/src/gcode/control/M999.cpp b/Marlin/src/gcode/control/M999.cpp
index b7d6db9f23..b4278fccad 100644
--- a/Marlin/src/gcode/control/M999.cpp
+++ b/Marlin/src/gcode/control/M999.cpp
@@ -36,7 +36,7 @@
  * existing command buffer.
  */
 void GcodeSuite::M999() {
-  marlin_state = MF_RUNNING;
+  marlin_state = MarlinState::MF_RUNNING;
   ui.reset_alert_level();
 
   if (parser.boolval('S')) return;
diff --git a/Marlin/src/lcd/extui/mks_ui/draw_printing.cpp b/Marlin/src/lcd/extui/mks_ui/draw_printing.cpp
index 345c5dd732..ee913d6465 100644
--- a/Marlin/src/lcd/extui/mks_ui/draw_printing.cpp
+++ b/Marlin/src/lcd/extui/mks_ui/draw_printing.cpp
@@ -294,7 +294,7 @@ void setProBarRate() {
     lv_label_set_text(bar1ValueText, public_buf_l);
     lv_obj_align(bar1ValueText, bar1, LV_ALIGN_CENTER, 0, 0);
 
-    if (marlin_state == MF_SD_COMPLETE) {
+    if (marlin_state == MarlinState::MF_SD_COMPLETE) {
       if (once_flag == 0) {
         stop_print_time();
 
@@ -309,7 +309,7 @@ void setProBarRate() {
           if (gCfgItems.finish_power_off) {
             gcode.process_subcommands_now(F("M1001"));
             queue.inject(F("M81"));
-            marlin_state = MF_RUNNING;
+            marlin_state = MarlinState::MF_RUNNING;
           }
         #endif
       }
diff --git a/Marlin/src/lcd/extui/mks_ui/draw_ui.cpp b/Marlin/src/lcd/extui/mks_ui/draw_ui.cpp
index 7408197f73..bd06e6c1f4 100644
--- a/Marlin/src/lcd/extui/mks_ui/draw_ui.cpp
+++ b/Marlin/src/lcd/extui/mks_ui/draw_ui.cpp
@@ -766,7 +766,7 @@ void GUI_RefreshPage() {
         disp_print_time();
         disp_fan_Zpos();
       }
-      if (printing_rate_update_flag || marlin_state == MF_SD_COMPLETE) {
+      if (printing_rate_update_flag || marlin_state == MarlinState::MF_SD_COMPLETE) {
         printing_rate_update_flag = false;
         if (!gcode_preview_over) setProBarRate();
       }
diff --git a/Marlin/src/lcd/extui/ui_api.cpp b/Marlin/src/lcd/extui/ui_api.cpp
index 1fcfabdd72..d89a09d8ad 100644
--- a/Marlin/src/lcd/extui/ui_api.cpp
+++ b/Marlin/src/lcd/extui/ui_api.cpp
@@ -1219,7 +1219,7 @@ namespace ExtUI {
   void onSurviveInKilled() {
     thermalManager.disable_all_heaters();
     flags.printer_killed = 0;
-    marlin_state = MF_RUNNING;
+    marlin_state = MarlinState::MF_RUNNING;
     //SERIAL_ECHOLNPGM("survived at: ", millis());
   }
 
diff --git a/Marlin/src/module/motion.cpp b/Marlin/src/module/motion.cpp
index 473d54cc38..4bbb182bc3 100644
--- a/Marlin/src/module/motion.cpp
+++ b/Marlin/src/module/motion.cpp
@@ -257,7 +257,7 @@ void report_current_position_projected() {
   AutoReporter<PositionReport> position_auto_reporter;
 #endif
 
-#if ANY(FULL_REPORT_TO_HOST_FEATURE, REALTIME_REPORTING_COMMANDS)
+#if ENABLED(REALTIME_REPORTING_COMMANDS)
 
   M_StateEnum M_State_grbl = M_INIT;
 
@@ -299,18 +299,18 @@ void report_current_position_projected() {
    */
   M_StateEnum grbl_state_for_marlin_state() {
     switch (marlin_state) {
-      case MF_INITIALIZING: return M_INIT;
-      case MF_SD_COMPLETE:  return M_ALARM;
-      case MF_WAITING:      return M_IDLE;
-      case MF_STOPPED:      return M_END;
-      case MF_RUNNING:      return M_RUNNING;
-      case MF_PAUSED:       return M_HOLD;
-      case MF_KILLED:       return M_ERROR;
-      default:              return M_IDLE;
+      case MarlinState::MF_INITIALIZING: return M_INIT;
+      case MarlinState::MF_SD_COMPLETE:  return M_ALARM;
+      case MarlinState::MF_WAITING:      return M_IDLE;
+      case MarlinState::MF_STOPPED:      return M_END;
+      case MarlinState::MF_RUNNING:      return M_RUNNING;
+      case MarlinState::MF_PAUSED:       return M_HOLD;
+      case MarlinState::MF_KILLED:       return M_ERROR;
+      default:                           return M_IDLE;
     }
   }
 
-#endif
+#endif // REALTIME_REPORTING_COMMANDS
 
 #if IS_KINEMATIC
 
diff --git a/Marlin/src/module/motion.h b/Marlin/src/module/motion.h
index f9748871f5..bb8f36446b 100644
--- a/Marlin/src/module/motion.h
+++ b/Marlin/src/module/motion.h
@@ -272,7 +272,7 @@ void report_current_position_projected();
   extern AutoReporter<PositionReport> position_auto_reporter;
 #endif
 
-#if ANY(FULL_REPORT_TO_HOST_FEATURE, REALTIME_REPORTING_COMMANDS)
+#if ENABLED(REALTIME_REPORTING_COMMANDS)
   #define HAS_GRBL_STATE 1
   /**
    * Machine states for GRBL or TinyG
@@ -305,11 +305,9 @@ void report_current_position_projected();
     }
   #endif
 
-  #if ENABLED(REALTIME_REPORTING_COMMANDS)
-    void quickpause_stepper();
-    void quickresume_stepper();
-  #endif
-#endif
+  void quickpause_stepper();
+  void quickresume_stepper();
+#endif // REALTIME_REPORTING_COMMANDS
 
 float get_move_distance(const xyze_pos_t &diff OPTARG(HAS_ROTATIONAL_AXES, bool &is_cartesian_move));
 
diff --git a/Marlin/src/module/planner.cpp b/Marlin/src/module/planner.cpp
index 0e45f55214..892258ff3b 100644
--- a/Marlin/src/module/planner.cpp
+++ b/Marlin/src/module/planner.cpp
@@ -799,8 +799,8 @@ void Planner::calculate_trapezoid_for_block(block_t * const block, const_float_t
   // Removing code to constrain values produces judder in direction-switching moves because the
   // current discrete stepping math diverges from physical motion under constant acceleration
   // when acceleration_steps_per_s2 is large compared to initial/final_rate.
-  NOLESS(initial_rate, long(MINIMAL_STEP_RATE));
-  NOLESS(final_rate,   long(MINIMAL_STEP_RATE));
+  NOLESS(initial_rate, uint32_t(MINIMAL_STEP_RATE));
+  NOLESS(final_rate,   uint32_t(MINIMAL_STEP_RATE));
   NOMORE(initial_rate, block->nominal_rate);  // NOTE: The nominal rate may be less than MINIMAL_STEP_RATE!
   NOMORE(final_rate,   block->nominal_rate);
 
diff --git a/Marlin/src/module/temperature.cpp b/Marlin/src/module/temperature.cpp
index 16b43f62f0..1b8ebeea69 100644
--- a/Marlin/src/module/temperature.cpp
+++ b/Marlin/src/module/temperature.cpp
@@ -1430,7 +1430,7 @@ int16_t Temperature::getHeaterPower(const heater_id_t heater_id) {
 //
 
 inline void loud_kill(FSTR_P const lcd_msg, const heater_id_t heater_id) {
-  marlin_state = MF_KILLED;
+  marlin_state = MarlinState::MF_KILLED;
   thermalManager.disable_all_heaters();
   #if HAS_BEEPER
     for (uint8_t i = 20; i--;) {
@@ -2077,7 +2077,7 @@ void Temperature::mintemp_error(const heater_id_t heater_id OPTARG(ERR_INCLUDE_T
  *  - Update the heated bed PID output value
  */
 void Temperature::task() {
-  if (marlin_state == MF_INITIALIZING) return hal.watchdog_refresh(); // If Marlin isn't started, at least reset the watchdog!
+  if (marlin_state == MarlinState::MF_INITIALIZING) return hal.watchdog_refresh(); // If Marlin isn't started, at least reset the watchdog!
 
   static bool no_reentry = false;  // Prevent recursion
   if (no_reentry) return;
diff --git a/Marlin/src/sd/cardreader.cpp b/Marlin/src/sd/cardreader.cpp
index 1431994093..c13ba37a96 100644
--- a/Marlin/src/sd/cardreader.cpp
+++ b/Marlin/src/sd/cardreader.cpp
@@ -497,7 +497,7 @@ void CardReader::mount() {
     cdroot();
   else {
     #if ANY(HAS_SD_DETECT, USB_FLASH_DRIVE_SUPPORT)
-      if (marlin_state != MF_INITIALIZING) LCD_ALERTMESSAGE(MSG_MEDIA_INIT_FAIL);
+      if (marlin_state != MarlinState::MF_INITIALIZING) LCD_ALERTMESSAGE(MSG_MEDIA_INIT_FAIL);
     #endif
   }
 
@@ -1412,8 +1412,8 @@ void CardReader::fileHasFinished() {
 
   endFilePrintNow(TERN_(SD_RESORT, true));
 
-  flag.sdprintdone = true;        // Stop getting bytes from the SD card
-  marlin_state = MF_SD_COMPLETE;  // Tell Marlin to enqueue M1001 soon
+  flag.sdprintdone = true;                    // Stop getting bytes from the SD card
+  marlin_state = MarlinState::MF_SD_COMPLETE; // Tell Marlin to enqueue M1001 soon
 }
 
 #if ENABLED(AUTO_REPORT_SD_STATUS)