Prevent longpress if a serious error is set

Firmware/ultralcd.cpp

@@ -8076,9 +8076,9 @@ uint8_t get_message_level()
 void menu_lcd_longpress_func(void)
 {
 	backlight_wake();
-    if (homing_flag || mesh_bed_leveling_flag || menu_menu == lcd_babystep_z || menu_menu == lcd_move_z)
+    if (homing_flag || mesh_bed_leveling_flag || menu_menu == lcd_babystep_z || menu_menu == lcd_move_z || menu_block_entering_on_serious_errors != SERIOUS_ERR_NONE)
     {
-        // disable longpress during re-entry, while homing or calibration
+        // disable longpress during re-entry, while homing, calibration or if a serious error
         lcd_quick_feedback();
         return;
     }