                   preview_buffer: "PreviewBuffer",
                   parent: Optional[tk.Widget] = None,
                   triggers: Optional["TriggerType"] = None) -> None:
          logger.debug("Initializing %s (parent: '%s')", self.__class__.__name__, parent)
          super().__init__(preview_buffer, triggers=triggers)
          self._is_standalone = parent is None
          self._initialized = False
 
</s> remove         self._initialized = not self._is_standalone
 </s> add         self._initialized = False </s> remove     def __init__(self, parent: tk.Frame, is_standalone: bool) -> None:
        logger.debug("Initializing %s (parent: '%s', is_standalone: %s)",
                     self.__class__.__name__, parent, is_standalone)
        super().__init__(parent)
 </s> add     def __init__(self, parent: tk.Frame, taskbar: Optional[ttk.Frame]) -> None:
        logger.debug("Initializing %s (parent: '%s', taskbar: %s)",
                     self.__class__.__name__, parent, taskbar)
        self._is_standalone = taskbar is None
        self._gui_mapped: List[tk.Widget] = []
        self._frame = tk.Frame(parent) if taskbar is None else taskbar
 </s> remove         self._taskbar = _Taskbar(self._master_frame, self._is_standalone)
 </s> add         self._taskbar = _Taskbar(self._master_frame, taskbar) </s> remove                  screen_dimensions: Tuple[int, int]) -> None:
 </s> add                  screen_dimensions: Tuple[int, int],
                 is_standalone: bool) -> None: </s> remove     def __init__(self, save_variable: tk.BooleanVar) -> None:
        logger.debug("Initializing %s: (save_variable: %s)",
                     self.__class__.__name__, save_variable)
 </s> add     def __init__(self, save_variable: tk.BooleanVar, is_standalone: bool) -> None:
        logger.debug("Initializing %s: (save_variable: %s, is_standalone: %s)",
                     self.__class__.__name__, save_variable, is_standalone)
        self._is_standalone = is_standalone
                 taskbar: Optional[ttk.Frame] = None,
                   preview_buffer: "PreviewBuffer",
                   parent: Optional[tk.Widget] = None,
                 taskbar: Optional[ttk.Frame] = None,
                   triggers: Optional["TriggerType"] = None) -> None:
          logger.debug("Initializing %s (parent: '%s')", self.__class__.__name__, parent)
          super().__init__(preview_buffer, triggers=triggers)
          self._is_standalone = parent is None
          self._initialized = False
keep add keep keep keep keep keep
 GUI - Preview updates
  - Training preview. Embed preview pop-out window
  - Bugfix - convert/extract previews 
lib/training/preview_tk.py