Try this:

from selenium import webdriver
from selenium.webdriver.chrome.options import Options

optionss = Options()
optionss.add_argument("--start-maximized")
optionss.add_argument("--disable-popup-blocking")
optionss.add_argument("--ignore-certificate-errors")
driver = webdriver.Chrome(options=optionss)

If you already doing this, please show us all code.