PyQt5 show hide is not working when shortcut is used

MLua

I am writing a QT application that can call up by short cut when I need, and hide when I no longer need it.
I have come with a sample code, it totally work for what I want. But the strange thing is when I change the input to QLineEdit (see line 28), show is not working.

So when I run the sample code with QLineEdit (self.input = QLineEdit), pressing "ctrl + o" can't properly re-show the windows, the windows popup but content is missing. Instead I need to click show from system tray.

In short, when QCheckBox is used, both shortcut and system tray click show can properly re-show. But when QLineEdit is used, shortcut re-show is not working.

Any idea of why? I am using Windows 11.

#!/usr/bin/env python
# -*- coding: utf-8 -*-

import sys
from PyQt5.QtWidgets import QApplication, QMainWindow, QLabel, QGridLayout, QWidget, QLineEdit, QSystemTrayIcon, \
    QSpacerItem, QSizePolicy, QMenu, QAction, QStyle, QCheckBox
from PyQt5.QtCore import QSize
import keyboard

class MainWindow(QMainWindow):
    input = None
    tray_icon = None

    def __init__(self):
        QMainWindow.__init__(self)

        self.setMinimumSize(QSize(480, 80))
        self.setWindowTitle("System Tray Application")
        central_widget = QWidget(self)
        self.setCentralWidget(central_widget)

        grid_layout = QGridLayout(self)
        central_widget.setLayout(grid_layout)
        grid_layout.addWidget(
            QLabel("Application, which can minimize to Tray", self), 0, 0)

        # ! QLineEdit is not working for show, but QCheckBox work !
        self.input = QLineEdit('Enter text here')
        # self.input = QCheckBox('Enter text here')
        grid_layout.addWidget(self.input, 1, 0)
        grid_layout.addItem(QSpacerItem(
            0, 0, QSizePolicy.Expanding, QSizePolicy.Expanding), 2, 0)

        self.tray_icon = QSystemTrayIcon(self)
        self.tray_icon.setIcon(
            self.style().standardIcon(QStyle.SP_ComputerIcon))

        show_action = QAction("Show", self)
        quit_action = QAction("Exit", self)
        hide_action = QAction("Hide", self)
        show_action.triggered.connect(self.show)
        hide_action.triggered.connect(self.hide)
        quit_action.triggered.connect(QApplication.instance().quit)
        tray_menu = QMenu()
        tray_menu.addAction(show_action)
        tray_menu.addAction(hide_action)
        tray_menu.addAction(quit_action)
        self.tray_icon.setContextMenu(tray_menu)
        self.tray_icon.show()

        keyboard.add_hotkey('ctrl+o', self.show_hotkey)

    def closeEvent(self, event):
        event.ignore()
        self.hide()
        self.input.hide()

    def show_hotkey(self):
        self.show
        self.activateWindow()
        self.raise_()
        self.input.setFocus()

    # def show_hotkey(self):
    #     self.input.setParent(None)  # Detach the widget from its parent
    #     self.show()
    #     self.input.setParent(self.centralWidget())  # Re-attach the widget to its parent
    #     self.input.show()  # Show the widget explicitly
    #     self.activateWindow()
    #     self.raise_()
    #     self.input.setFocus()  # Set focus to the QLineEdit


if __name__ == "__main__":
    app = QApplication(sys.argv)
    window = MainWindow()
    window.show()
    sys.exit(app.exec_())