PREVENT_DANGEROUS_EXTRUDE => PREVENT_COLD_EXTRUSION

Also improve the documentation of this and related options, and set
EXTRUDE_MINTEMP to 170 everywhere.

Marlin/Conditionals_post.h

@@ -522,8 +522,8 @@
   #define HAS_THERMALLY_PROTECTED_BED (HAS_TEMP_BED && HAS_HEATER_BED && ENABLED(THERMAL_PROTECTION_BED))
 
   /**
-   * This value is used by M109 when trying to calculate a ballpark safe margin
+   * This setting is also used by M109 when trying to calculate
-   * to prevent wait-forever situation.
+   * a ballpark safe margin to prevent wait-forever situation.
    */
   #ifndef EXTRUDE_MINTEMP
     #define EXTRUDE_MINTEMP 170

Marlin/Configuration.h

@@ -347,14 +347,16 @@
 
 // @section extruder
 
-//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
+// This option prevents extrusion if the temperature is below EXTRUDE_MINTEMP.
-//can be software-disabled for whatever purposes by
+// It also enables the M302 command to set the minimum extrusion temperature
-#define PREVENT_DANGEROUS_EXTRUDE
+// or to allow moving the extruder regardless of the hotend temperature.
-//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
+// *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
-#define PREVENT_LENGTHY_EXTRUDE
+#define PREVENT_COLD_EXTRUSION
-
 #define EXTRUDE_MINTEMP 170
-#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH) //prevent extrusion of very large distances.
+
+// This option prevents a single extrusion longer than EXTRUDE_MAXLENGTH.
+#define PREVENT_LENGTHY_EXTRUDE
+#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH)
 
 //===========================================================================
 //======================== Thermal Runaway Protection =======================

Marlin/Marlin_main.cpp

@@ -5844,7 +5844,7 @@ inline void gcode_M226() {
 
 #endif // HAS_LCD_CONTRAST
 
-#if ENABLED(PREVENT_DANGEROUS_EXTRUDE)
+#if ENABLED(PREVENT_COLD_EXTRUSION)
 
   /**
    * M302: Allow cold extrudes, or set the minimum extrude temperature
@@ -5879,7 +5879,7 @@ inline void gcode_M226() {
     }
   }
 
-#endif // PREVENT_DANGEROUS_EXTRUDE
+#endif // PREVENT_COLD_EXTRUSION
 
 /**
  * M303: PID relay autotune
@@ -7549,11 +7549,11 @@ void process_next_command() {
           break;
       #endif // HAS_LCD_CONTRAST
 
-      #if ENABLED(PREVENT_DANGEROUS_EXTRUDE)
+      #if ENABLED(PREVENT_COLD_EXTRUSION)
         case 302: // allow cold extrudes, or set the minimum extrude temperature
           gcode_M302();
           break;
-      #endif // PREVENT_DANGEROUS_EXTRUDE
+      #endif // PREVENT_COLD_EXTRUSION
 
       case 303: // M303 PID autotune
         gcode_M303();
@@ -8121,7 +8121,7 @@ void mesh_line_to_destination(float fr_mm_s, uint8_t x_splits = 0xff, uint8_t y_
 
 #endif // !DELTA && !SCARA
 
-#if ENABLED(PREVENT_DANGEROUS_EXTRUDE)
+#if ENABLED(PREVENT_COLD_EXTRUSION)
 
   inline void prevent_dangerous_extrude(float& curr_e, float& dest_e) {
     if (DEBUGGING(DRYRUN)) return;
@@ -8142,7 +8142,7 @@ void mesh_line_to_destination(float fr_mm_s, uint8_t x_splits = 0xff, uint8_t y_
     }
   }
 
-#endif // PREVENT_DANGEROUS_EXTRUDE
+#endif // PREVENT_COLD_EXTRUSION
 
 /**
  * Prepare a single move and get ready for the next one
@@ -8154,7 +8154,7 @@ void prepare_move_to_destination() {
   clamp_to_software_endstops(destination);
   refresh_cmd_timeout();
 
-  #if ENABLED(PREVENT_DANGEROUS_EXTRUDE)
+  #if ENABLED(PREVENT_COLD_EXTRUSION)
     prevent_dangerous_extrude(current_position[E_AXIS], destination[E_AXIS]);
   #endif
 

Marlin/SanityCheck.h

@@ -135,6 +135,8 @@
   #error "Z_RAISE_PROBE_DEPLOY_STOW and Z_RAISE_BETWEEN_PROBINGS are now Z_PROBE_DEPLOY_HEIGHT and Z_PROBE_TRAVEL_HEIGHT Please update your configuration."
 #elif !defined(MIN_SEGMENTS_FOR_MOVE)
   #error "\"dropsegments\" is replaced with MIN_SEGMENTS_FOR_MOVE (and increases by 1). Please update Configuration_adv.h."
+#elif defined(PREVENT_DANGEROUS_EXTRUDE)
+  #error "PREVENT_DANGEROUS_EXTRUDE is now PREVENT_COLD_EXTRUSION. Please update your configuration."
 #endif
 
 /**

Marlin/example_configurations/Cartesio/Configuration.h

@@ -347,14 +347,16 @@
 
 // @section extruder
 
-//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
+// This option prevents extrusion if the temperature is below EXTRUDE_MINTEMP.
-//can be software-disabled for whatever purposes by
+// It also enables the M302 command to set the minimum extrusion temperature
-#define PREVENT_DANGEROUS_EXTRUDE
+// or to allow moving the extruder regardless of the hotend temperature.
-//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
+// *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
-#define PREVENT_LENGTHY_EXTRUDE
+#define PREVENT_COLD_EXTRUSION
+#define EXTRUDE_MINTEMP 170
 
-#define EXTRUDE_MINTEMP 18
+// This option prevents a single extrusion longer than EXTRUDE_MAXLENGTH.
-#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH) //prevent extrusion of very large distances.
+#define PREVENT_LENGTHY_EXTRUDE
+#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH)
 
 //===========================================================================
 //======================== Thermal Runaway Protection =======================

Marlin/example_configurations/Felix/Configuration.h

@@ -329,14 +329,16 @@
 
 // @section extruder
 
-//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
+// This option prevents extrusion if the temperature is below EXTRUDE_MINTEMP.
-//can be software-disabled for whatever purposes by
+// It also enables the M302 command to set the minimum extrusion temperature
-#define PREVENT_DANGEROUS_EXTRUDE
+// or to allow moving the extruder regardless of the hotend temperature.
-//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
+// *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
-#define PREVENT_LENGTHY_EXTRUDE
+#define PREVENT_COLD_EXTRUSION
-
 #define EXTRUDE_MINTEMP 170
-#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH) //prevent extrusion of very large distances.
+
+// This option prevents a single extrusion longer than EXTRUDE_MAXLENGTH.
+#define PREVENT_LENGTHY_EXTRUDE
+#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH)
 
 //===========================================================================
 //======================== Thermal Runaway Protection =======================

Marlin/example_configurations/Felix/DUAL/Configuration.h

@@ -327,14 +327,16 @@
 
 // @section extruder
 
-//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
+// This option prevents extrusion if the temperature is below EXTRUDE_MINTEMP.
-//can be software-disabled for whatever purposes by
+// It also enables the M302 command to set the minimum extrusion temperature
-#define PREVENT_DANGEROUS_EXTRUDE
+// or to allow moving the extruder regardless of the hotend temperature.
-//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
+// *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
-#define PREVENT_LENGTHY_EXTRUDE
+#define PREVENT_COLD_EXTRUSION
-
 #define EXTRUDE_MINTEMP 170
-#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH) //prevent extrusion of very large distances.
+
+// This option prevents a single extrusion longer than EXTRUDE_MAXLENGTH.
+#define PREVENT_LENGTHY_EXTRUDE
+#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH)
 
 //===========================================================================
 //======================== Thermal Runaway Protection =======================

Marlin/example_configurations/Hephestos/Configuration.h

@@ -339,14 +339,16 @@
 
 // @section extruder
 
-//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
+// This option prevents extrusion if the temperature is below EXTRUDE_MINTEMP.
-//can be software-disabled for whatever purposes by
+// It also enables the M302 command to set the minimum extrusion temperature
-#define PREVENT_DANGEROUS_EXTRUDE
+// or to allow moving the extruder regardless of the hotend temperature.
-//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
+// *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
-#define PREVENT_LENGTHY_EXTRUDE
+#define PREVENT_COLD_EXTRUSION
-
 #define EXTRUDE_MINTEMP 170
-#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH) //prevent extrusion of very large distances.
+
+// This option prevents a single extrusion longer than EXTRUDE_MAXLENGTH.
+#define PREVENT_LENGTHY_EXTRUDE
+#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH)
 
 //===========================================================================
 //======================== Thermal Runaway Protection =======================

Marlin/example_configurations/Hephestos_2/Configuration.h

@@ -341,14 +341,16 @@
 
 // @section extruder
 
-//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
+// This option prevents extrusion if the temperature is below EXTRUDE_MINTEMP.
-//can be software-disabled for whatever purposes by
+// It also enables the M302 command to set the minimum extrusion temperature
-#define PREVENT_DANGEROUS_EXTRUDE
+// or to allow moving the extruder regardless of the hotend temperature.
-//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
+// *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
-#define PREVENT_LENGTHY_EXTRUDE
+#define PREVENT_COLD_EXTRUSION
-
 #define EXTRUDE_MINTEMP 170
-#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH) //prevent extrusion of very large distances.
+
+// This option prevents a single extrusion longer than EXTRUDE_MAXLENGTH.
+#define PREVENT_LENGTHY_EXTRUDE
+#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH)
 
 //===========================================================================
 //======================== Thermal Runaway Protection =======================

Marlin/example_configurations/K8200/Configuration.h

@@ -364,14 +364,16 @@
 
 // @section extruder
 
-//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
+// This option prevents extrusion if the temperature is below EXTRUDE_MINTEMP.
-//can be software-disabled for whatever purposes by
+// It also enables the M302 command to set the minimum extrusion temperature
-#define PREVENT_DANGEROUS_EXTRUDE
+// or to allow moving the extruder regardless of the hotend temperature.
-//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
+// *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
-#define PREVENT_LENGTHY_EXTRUDE
+#define PREVENT_COLD_EXTRUSION
-
 #define EXTRUDE_MINTEMP 170
-#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH) //prevent extrusion of very large distances.
+
+// This option prevents a single extrusion longer than EXTRUDE_MAXLENGTH.
+#define PREVENT_LENGTHY_EXTRUDE
+#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH)
 
 //===========================================================================
 //======================== Thermal Runaway Protection =======================

Marlin/example_configurations/K8400/Configuration.h

@@ -347,14 +347,16 @@
 
 // @section extruder
 
-//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
+// This option prevents extrusion if the temperature is below EXTRUDE_MINTEMP.
-//can be software-disabled for whatever purposes by
+// It also enables the M302 command to set the minimum extrusion temperature
-#define PREVENT_DANGEROUS_EXTRUDE
+// or to allow moving the extruder regardless of the hotend temperature.
-//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
+// *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
-#define PREVENT_LENGTHY_EXTRUDE
+#define PREVENT_COLD_EXTRUSION
+#define EXTRUDE_MINTEMP 170
 
-#define EXTRUDE_MINTEMP 160
+// This option prevents a single extrusion longer than EXTRUDE_MAXLENGTH.
-#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH) //prevent extrusion of very large distances.
+#define PREVENT_LENGTHY_EXTRUDE
+#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH)
 
 //===========================================================================
 //======================== Thermal Runaway Protection =======================

Marlin/example_configurations/K8400/Dual-head/Configuration.h

@@ -347,14 +347,16 @@
 
 // @section extruder
 
-//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
+// This option prevents extrusion if the temperature is below EXTRUDE_MINTEMP.
-//can be software-disabled for whatever purposes by
+// It also enables the M302 command to set the minimum extrusion temperature
-#define PREVENT_DANGEROUS_EXTRUDE
+// or to allow moving the extruder regardless of the hotend temperature.
-//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
+// *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
-#define PREVENT_LENGTHY_EXTRUDE
+#define PREVENT_COLD_EXTRUSION
+#define EXTRUDE_MINTEMP 170
 
-#define EXTRUDE_MINTEMP 160
+// This option prevents a single extrusion longer than EXTRUDE_MAXLENGTH.
-#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH) //prevent extrusion of very large distances.
+#define PREVENT_LENGTHY_EXTRUDE
+#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH)
 
 //===========================================================================
 //======================== Thermal Runaway Protection =======================

Marlin/example_configurations/RepRapWorld/Megatronics/Configuration.h

@@ -347,14 +347,16 @@
 
 // @section extruder
 
-//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
+// This option prevents extrusion if the temperature is below EXTRUDE_MINTEMP.
-//can be software-disabled for whatever purposes by
+// It also enables the M302 command to set the minimum extrusion temperature
-#define PREVENT_DANGEROUS_EXTRUDE
+// or to allow moving the extruder regardless of the hotend temperature.
-//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
+// *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
-#define PREVENT_LENGTHY_EXTRUDE
+#define PREVENT_COLD_EXTRUSION
-
 #define EXTRUDE_MINTEMP 170
-#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH) //prevent extrusion of very large distances.
+
+// This option prevents a single extrusion longer than EXTRUDE_MAXLENGTH.
+#define PREVENT_LENGTHY_EXTRUDE
+#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH)
 
 //===========================================================================
 //======================== Thermal Runaway Protection =======================

Marlin/example_configurations/RigidBot/Configuration.h

@@ -344,14 +344,16 @@
 
 // @section extruder
 
-//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
+// This option prevents extrusion if the temperature is below EXTRUDE_MINTEMP.
-//can be software-disabled for whatever purposes by
+// It also enables the M302 command to set the minimum extrusion temperature
-#define PREVENT_DANGEROUS_EXTRUDE
+// or to allow moving the extruder regardless of the hotend temperature.
-//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
+// *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
-#define PREVENT_LENGTHY_EXTRUDE
+#define PREVENT_COLD_EXTRUSION
-
 #define EXTRUDE_MINTEMP 170
-#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH) //prevent extrusion of very large distances.
+
+// This option prevents a single extrusion longer than EXTRUDE_MAXLENGTH.
+#define PREVENT_LENGTHY_EXTRUDE
+#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH)
 
 //===========================================================================
 //======================== Thermal Runaway Protection =======================

Marlin/example_configurations/SCARA/Configuration.h

@@ -355,14 +355,16 @@
 
 // @section extruder
 
-//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
+// This option prevents extrusion if the temperature is below EXTRUDE_MINTEMP.
-//can be software-disabled for whatever purposes by
+// It also enables the M302 command to set the minimum extrusion temperature
-//#define PREVENT_DANGEROUS_EXTRUDE
+// or to allow moving the extruder regardless of the hotend temperature.
-//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
+// *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
-#define PREVENT_LENGTHY_EXTRUDE
+#define PREVENT_COLD_EXTRUSION
+#define EXTRUDE_MINTEMP 170
 
-#define EXTRUDE_MINTEMP 150
+// This option prevents a single extrusion longer than EXTRUDE_MAXLENGTH.
-#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH) //prevent extrusion of very large distances.
+#define PREVENT_LENGTHY_EXTRUDE
+#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH)
 
 //===========================================================================
 //======================== Thermal Runaway Protection =======================

Marlin/example_configurations/TAZ4/Configuration.h

@@ -368,14 +368,16 @@
 
 // @section extruder
 
-//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
+// This option prevents extrusion if the temperature is below EXTRUDE_MINTEMP.
-//can be software-disabled for whatever purposes by
+// It also enables the M302 command to set the minimum extrusion temperature
-#define PREVENT_DANGEROUS_EXTRUDE
+// or to allow moving the extruder regardless of the hotend temperature.
-//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
+// *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
-#define PREVENT_LENGTHY_EXTRUDE
+#define PREVENT_COLD_EXTRUSION
-
 #define EXTRUDE_MINTEMP 170
-#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH) //prevent extrusion of very large distances.
+
+// This option prevents a single extrusion longer than EXTRUDE_MAXLENGTH.
+#define PREVENT_LENGTHY_EXTRUDE
+#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH)
 
 //===========================================================================
 //======================== Thermal Runaway Protection =======================

Marlin/example_configurations/WITBOX/Configuration.h

@@ -339,14 +339,16 @@
 
 // @section extruder
 
-//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
+// This option prevents extrusion if the temperature is below EXTRUDE_MINTEMP.
-//can be software-disabled for whatever purposes by
+// It also enables the M302 command to set the minimum extrusion temperature
-#define PREVENT_DANGEROUS_EXTRUDE
+// or to allow moving the extruder regardless of the hotend temperature.
-//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
+// *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
-#define PREVENT_LENGTHY_EXTRUDE
+#define PREVENT_COLD_EXTRUSION
-
 #define EXTRUDE_MINTEMP 170
-#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH) //prevent extrusion of very large distances.
+
+// This option prevents a single extrusion longer than EXTRUDE_MAXLENGTH.
+#define PREVENT_LENGTHY_EXTRUDE
+#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH)
 
 //===========================================================================
 //======================== Thermal Runaway Protection =======================

Marlin/example_configurations/adafruit/ST7565/Configuration.h

@@ -347,14 +347,16 @@
 
 // @section extruder
 
-//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
+// This option prevents extrusion if the temperature is below EXTRUDE_MINTEMP.
-//can be software-disabled for whatever purposes by
+// It also enables the M302 command to set the minimum extrusion temperature
-#define PREVENT_DANGEROUS_EXTRUDE
+// or to allow moving the extruder regardless of the hotend temperature.
-//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
+// *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
-#define PREVENT_LENGTHY_EXTRUDE
+#define PREVENT_COLD_EXTRUSION
-
 #define EXTRUDE_MINTEMP 170
-#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH) //prevent extrusion of very large distances.
+
+// This option prevents a single extrusion longer than EXTRUDE_MAXLENGTH.
+#define PREVENT_LENGTHY_EXTRUDE
+#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH)
 
 //===========================================================================
 //======================== Thermal Runaway Protection =======================

Marlin/example_configurations/delta/biv2.5/Configuration.h

@@ -347,14 +347,16 @@
 
 // @section extruder
 
-//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
+// This option prevents extrusion if the temperature is below EXTRUDE_MINTEMP.
-//can be software-disabled for whatever purposes by
+// It also enables the M302 command to set the minimum extrusion temperature
-#define PREVENT_DANGEROUS_EXTRUDE
+// or to allow moving the extruder regardless of the hotend temperature.
-//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
+// *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
-#define PREVENT_LENGTHY_EXTRUDE
+#define PREVENT_COLD_EXTRUSION
-
 #define EXTRUDE_MINTEMP 170
-#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH) //prevent extrusion of very large distances.
+
+// This option prevents a single extrusion longer than EXTRUDE_MAXLENGTH.
+#define PREVENT_LENGTHY_EXTRUDE
+#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH)
 
 //===========================================================================
 //======================== Thermal Runaway Protection =======================

Marlin/example_configurations/delta/generic/Configuration.h

@@ -347,14 +347,16 @@
 
 // @section extruder
 
-//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
+// This option prevents extrusion if the temperature is below EXTRUDE_MINTEMP.
-//can be software-disabled for whatever purposes by
+// It also enables the M302 command to set the minimum extrusion temperature
-#define PREVENT_DANGEROUS_EXTRUDE
+// or to allow moving the extruder regardless of the hotend temperature.
-//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
+// *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
-#define PREVENT_LENGTHY_EXTRUDE
+#define PREVENT_COLD_EXTRUSION
-
 #define EXTRUDE_MINTEMP 170
-#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH) //prevent extrusion of very large distances.
+
+// This option prevents a single extrusion longer than EXTRUDE_MAXLENGTH.
+#define PREVENT_LENGTHY_EXTRUDE
+#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH)
 
 //===========================================================================
 //======================== Thermal Runaway Protection =======================

Marlin/example_configurations/delta/kossel_mini/Configuration.h

@@ -347,14 +347,16 @@
 
 // @section extruder
 
-//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
+// This option prevents extrusion if the temperature is below EXTRUDE_MINTEMP.
-//can be software-disabled for whatever purposes by
+// It also enables the M302 command to set the minimum extrusion temperature
-#define PREVENT_DANGEROUS_EXTRUDE
+// or to allow moving the extruder regardless of the hotend temperature.
-//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
+// *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
-#define PREVENT_LENGTHY_EXTRUDE
+#define PREVENT_COLD_EXTRUSION
-
 #define EXTRUDE_MINTEMP 170
-#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH) //prevent extrusion of very large distances.
+
+// This option prevents a single extrusion longer than EXTRUDE_MAXLENGTH.
+#define PREVENT_LENGTHY_EXTRUDE
+#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH)
 
 //===========================================================================
 //======================== Thermal Runaway Protection =======================

Marlin/example_configurations/delta/kossel_pro/Configuration.h

@@ -336,14 +336,16 @@
 
 // @section extruder
 
-//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
+// This option prevents extrusion if the temperature is below EXTRUDE_MINTEMP.
-//can be software-disabled for whatever purposes by
+// It also enables the M302 command to set the minimum extrusion temperature
-#define PREVENT_DANGEROUS_EXTRUDE
+// or to allow moving the extruder regardless of the hotend temperature.
-//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
+// *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
-#define PREVENT_LENGTHY_EXTRUDE
+#define PREVENT_COLD_EXTRUSION
-
 #define EXTRUDE_MINTEMP 170
-#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH) //prevent extrusion of very large distances.
+
+// This option prevents a single extrusion longer than EXTRUDE_MAXLENGTH.
+#define PREVENT_LENGTHY_EXTRUDE
+#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH)
 
 //===========================================================================
 //======================== Thermal Runaway Protection =======================

Marlin/example_configurations/delta/kossel_xl/Configuration.h

@@ -345,14 +345,16 @@
 
 // @section extruder
 
-//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
+// This option prevents extrusion if the temperature is below EXTRUDE_MINTEMP.
-//can be software-disabled for whatever purposes by
+// It also enables the M302 command to set the minimum extrusion temperature
-#define PREVENT_DANGEROUS_EXTRUDE
+// or to allow moving the extruder regardless of the hotend temperature.
-//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
+// *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
-#define PREVENT_LENGTHY_EXTRUDE
+#define PREVENT_COLD_EXTRUSION
-
 #define EXTRUDE_MINTEMP 170
-#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH) //prevent extrusion of very large distances.
+
+// This option prevents a single extrusion longer than EXTRUDE_MAXLENGTH.
+#define PREVENT_LENGTHY_EXTRUDE
+#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH)
 
 //===========================================================================
 //======================== Thermal Runaway Protection =======================

Marlin/example_configurations/makibox/Configuration.h

@@ -350,14 +350,16 @@
 
 // @section extruder
 
-//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
+// This option prevents extrusion if the temperature is below EXTRUDE_MINTEMP.
-//can be software-disabled for whatever purposes by
+// It also enables the M302 command to set the minimum extrusion temperature
-#define PREVENT_DANGEROUS_EXTRUDE
+// or to allow moving the extruder regardless of the hotend temperature.
-//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
+// *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
-#define PREVENT_LENGTHY_EXTRUDE
+#define PREVENT_COLD_EXTRUSION
-
 #define EXTRUDE_MINTEMP 170
-#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH) //prevent extrusion of very large distances.
+
+// This option prevents a single extrusion longer than EXTRUDE_MAXLENGTH.
+#define PREVENT_LENGTHY_EXTRUDE
+#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH)
 
 //===========================================================================
 //======================== Thermal Runaway Protection =======================

Marlin/example_configurations/tvrrug/Round2/Configuration.h

@@ -337,14 +337,16 @@
 
 // @section extruder
 
-//this prevents dangerous Extruder moves, i.e. if the temperature is under the limit
+// This option prevents extrusion if the temperature is below EXTRUDE_MINTEMP.
-//can be software-disabled for whatever purposes by
+// It also enables the M302 command to set the minimum extrusion temperature
-#define PREVENT_DANGEROUS_EXTRUDE
+// or to allow moving the extruder regardless of the hotend temperature.
-//if PREVENT_DANGEROUS_EXTRUDE is on, you can still disable (uncomment) very long bits of extrusion separately.
+// *** IT IS HIGHLY RECOMMENDED TO LEAVE THIS OPTION ENABLED! ***
-#define PREVENT_LENGTHY_EXTRUDE
+#define PREVENT_COLD_EXTRUSION
-
 #define EXTRUDE_MINTEMP 170
-#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH) //prevent extrusion of very large distances.
+
+// This option prevents a single extrusion longer than EXTRUDE_MAXLENGTH.
+#define PREVENT_LENGTHY_EXTRUDE
+#define EXTRUDE_MAXLENGTH (X_MAX_LENGTH+Y_MAX_LENGTH)
 
 //===========================================================================
 //======================== Thermal Runaway Protection =======================

Marlin/planner.cpp

@@ -573,7 +573,7 @@ void Planner::check_axes_activity() {
 
   long de = target[E_AXIS] - position[E_AXIS];
 
-  #if ENABLED(PREVENT_DANGEROUS_EXTRUDE)
+  #if ENABLED(PREVENT_COLD_EXTRUSION)
     if (de) {
       if (thermalManager.tooColdToExtrude(extruder)) {
         position[E_AXIS] = target[E_AXIS]; // Behave as if the move really took place, but ignore E part

Marlin/temperature.cpp

@@ -108,7 +108,7 @@ unsigned char Temperature::soft_pwm_bed;
   millis_t Temperature::watch_bed_next_ms = 0;
 #endif
 
-#if ENABLED(PREVENT_DANGEROUS_EXTRUDE)
+#if ENABLED(PREVENT_COLD_EXTRUSION)
   bool Temperature::allow_cold_extrude = false;
   float Temperature::extrude_min_temp = EXTRUDE_MINTEMP;
 #endif

Marlin/temperature.h

@@ -121,7 +121,7 @@ class Temperature {
       static millis_t watch_bed_next_ms;
     #endif
 
-    #if ENABLED(PREVENT_DANGEROUS_EXTRUDE)
+    #if ENABLED(PREVENT_COLD_EXTRUSION)
       static bool allow_cold_extrude;
       static float extrude_min_temp;
       static bool tooColdToExtrude(uint8_t e) {