can't use sendkeys or element.click() when browser background,only works when using javascripts

[netgr]

the code run normally on original chromedriver when i used on version 115, since i changed to UC(to bypass CF),all sendkeys or click() not works WHEN browser running in background. but when i switch the browser to the front ,sendkeys and click() all works again.
why,and any suggestion?
BTW,in my case ,i use multithread to open multi brower instances ,each one has its own account login of same website.

if name == "main":
drivers = []

for account in list_accounts:

    ucoptions = uc.ChromeOptions()
    ucoptions.add_argument(f'--proxy-server=http://{proxy.http_proxy}')
    print(proxy.http_proxy,account)
    ucoptions.page_load_strategy = 'eager'

    jsusername = account["username"]

    driver = uc.Chrome(version_main=130, use_subprocess=True,
                  browser_executable_path=fr"C:\Users\admin\Desktop\scan\chrome_win32{jsusername}\chrome{jsusername}.exe",
                       options=ucoptions)

    drivers.append(driver)
    time.sleep(5)

threads = [Thread(target=open_login, args=(driver, account)) for driver, account in zip(drivers, list_accounts)]

for thread in threads:
    thread.daemon = True
    time.sleep(120)
    thread.start()

for thread in threads:
    thread.join()


for driver in drivers:
    print(driver)
    # driver.quit()