[Bug] window flash when update images in a thread about pysimplegui HOT 4 CLOSED

import threading
import cv2
import PySimpleGUI as sg

def RecordFun():
    global recording
    for i in range(1000):
        if recording:
            ret, frame = cap.read()
            imgbytes = cv2.imencode('.png', frame)[1].tobytes()  # ditto
            window.write_event_value("Update", imgbytes)
        else:
            break
    window.write_event_value("Done", None)

sg.theme('Black')

# define the window layout
layout = [[sg.Text('OpenCV Demo', size=(40, 1), justification='center', font='Helvetica 20')],
          [sg.Image(filename='', key='image')],
          [sg.Button('Record', size=(10, 1), font='Helvetica 14'),
           sg.Button('Stop', size=(10, 1), font='Helvetica 14'),
           sg.Button('Exit', size=(10, 1), font='Helvetica 14'), ]]

# create the window and show it without the plot
window = sg.Window('Demo Application - OpenCV Integration',
                   layout, location=(800, 400), enable_close_attempted_event=True)

# ---===--- Event LOOP Read and display frames, operate the GUI --- #
cap = cv2.VideoCapture(0)
recording, ending = False, False

while True:

    event, values = window.read(timeout=20)

    if event == sg.WINDOW_CLOSE_ATTEMPTED_EVENT or event == 'Exit':
        if not recording:
            break
        recording = False
        ending = True

    elif event == 'Record' and not recording:
        window['Record'].update(disabled=True)
        recording = True
        thread_IMloop = threading.Thread(target=RecordFun, daemon=True)
        thread_IMloop.start()

    elif event == "Stop":
        recording = False
        window['Record'].update(disabled=False)

    elif event == "Update":
        imgbytes = values[event]
        window['image'].update(data=imgbytes)

    elif event == "Done":
        window['Record'].update(disabled=False)
        if ending:
            break

window.close()
cap.release()