When the Paste Large Text button is clicked consecutively (or its corresponding shortcut key is triggered repeatedly), a new tkinter window is created each time.
连续点击大文本粘贴按钮（或反复按下对应快捷键）时，每次都会创建一个新的 tkinter 窗口。
After the second window is created, the previously opened window(s) can no longer close properly, and pasting text into their input boxes also stops working.
当第二个窗口创建后，之前打开的窗口会无法正常关闭，同时也无法再将文本粘贴到它们的输入框中。
All previously created windows remain visible but become non‑functional, and they cannot be closed via normal means (e.g., close button or programmatic close).
所有先前创建的窗口虽然仍然可见，但已完全失效，也无法通过正常方式（如关闭按钮或程序内关闭）将它们关闭。
The expected behavior is that clicking the button or pressing the shortcut while a "Paste Large Text" window is already open should either:
- bring the existing window to the front instead of creating a new one, or
close the previous window automatically before opening a new one.
预期行为是：当“大文本粘贴”窗口已经打开时，再次点击按钮或按下快捷键应该：
- 将已有窗口提到前台，而不是创建新窗口，或者
在打开新窗口前自动关闭之前的窗口。
When the Paste Large Text button is clicked consecutively (or its corresponding shortcut key is triggered repeatedly), a new tkinter window is created each time.
连续点击大文本粘贴按钮（或反复按下对应快捷键）时，每次都会创建一个新的 tkinter 窗口。
After the second window is created, the previously opened window(s) can no longer close properly, and pasting text into their input boxes also stops working.
当第二个窗口创建后，之前打开的窗口会无法正常关闭，同时也无法再将文本粘贴到它们的输入框中。
All previously created windows remain visible but become non‑functional, and they cannot be closed via normal means (e.g., close button or programmatic close).
所有先前创建的窗口虽然仍然可见，但已完全失效，也无法通过正常方式（如关闭按钮或程序内关闭）将它们关闭。
The expected behavior is that clicking the button or pressing the shortcut while a "Paste Large Text" window is already open should either:
close the previous window automatically before opening a new one.预期行为是：当“大文本粘贴”窗口已经打开时，再次点击按钮或按下快捷键应该：
在打开新窗口前自动关闭之前的窗口。