Autentiseringstavle og subtraktorkoder har minimum to koder

soitool/modules/code_table_base.py

@@ -221,10 +221,10 @@ class CodeTableBase(ModuleBase, QTableWidget, metaclass=Meta):
             event.modifiers() == Qt.ControlModifier
             and event.key() == Qt.Key_Underscore
         ):
-            # If at least one row (+ headline-row) exists and a row other than
+            # If at least two rows (+ headline-row) exists and a row other than
             # headline-row is selected
             row_index = self.currentRow()
-            if self.rowCount() > 2 and row_index != 0 and row_index != -1:
+            if self.rowCount() > 3 and row_index != 0 and row_index != -1:
                 self.remove_row(row_index)
         else:
             super().keyPressEvent(event)