diff --git a/plugins/USBPrinting/USBPrinterOutputDeviceManager.py b/plugins/USBPrinting/USBPrinterOutputDeviceManager.py
index 2adacde743..b8286e7af5 100644
--- a/plugins/USBPrinting/USBPrinterOutputDeviceManager.py
+++ b/plugins/USBPrinting/USBPrinterOutputDeviceManager.py
@@ -131,14 +131,12 @@ class USBPrinterOutputDeviceManager(QObject, SignalEmitter, OutputDevicePlugin,
         # Check whether getGlobalContainerStack() returns None or not...
         global_container_stack = Application.getInstance().getGlobalContainerStack()
         if not global_container_stack:
-            Logger.log("c", "getGlobalContainerStack() returned None")
-            Logger.log("i", "Closing firmware-updater UI as a consequence")
+            Logger.log("e", "There is no global container stack. Can not update firmware.")
             self._firmware_view.close()
         
-        # Detecting id of the current machine
+        # The bottom of the containerstack is the machine definition
         machine_id = global_container_stack.getBottom().id
         
-        # Detecting whether it has a heated bed
         machine_has_heated_bed = global_container_stack.getProperty("machine_heated_bed", "value")
         
         if platform.system() == "Linux":