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👤 UC Mode

UC Mode 👤

👤 SeleniumBase UC Mode (Undetected-Chromedriver Mode) allows bots to appear human, which lets them evade detection from anti-bot services that try to block them or trigger CAPTCHAs on various websites.

👤 UC Mode is based on undetected-chromedriver, but includes multiple updates, fixes, and improvements to support a wider range of features and edge cases:

  • Includes driver version-detection & management.
  • Allows mismatched browser/driver versions.
  • Automatically changes the user agent to prevent detection. (HeadlessChrome to Chrome)
  • Automatically disconnects chromedriver from Chrome as needed. (And reconnects)
  • Supports multithreaded tests in parallel via pytest-xdist.
  • Adjusts configuration based on the environment. (Linux/Ubuntu vs Windows vs macOS)
  • Has options for setting proxy and proxy-with-auth.
  • Has ways of adjusting timings from default values.
  • Includes multiple ways of structuring test scripts.

👤 Here's an example with the Driver manager:

from seleniumbase import Driver

driver = Driver(uc=True)
driver.uc_open_with_reconnect("", 5)

👤 Here's an example with the SB manager: (Has more methods than the Driver format, and also quits the driver automatically after the with block ends.)

from seleniumbase import SB

with SB(uc=True) as sb:
    sb.driver.uc_open_with_reconnect("", 5)

👤 Here's a longer example, which includes retries and a captcha-click failsafe for bypassing detection:

from seleniumbase import SB

with SB(uc=True, test=True) as sb:
    if not sb.is_text_visible("OH YEAH, you passed!", "h1"):
            "", reconnect_time=3
    if not sb.is_text_visible("OH YEAH, you passed!", "h1"):
        if sb.is_element_visible('iframe[src*="challenge"]'):
            with sb.frame_switch('iframe[src*="challenge"]'):
    sb.assert_text("OH YEAH, you passed!", "h1", timeout=3)

👤 Here's an example where clicking the checkbox is required, even for humans: (Commonly seen with forms that are CAPTCHA-protected.)

from seleniumbase import SB

def open_the_turnstile_page(sb):
        "", reconnect_time=2.5,

def click_turnstile_and_verify(sb):
    sb.assert_element("img#captcha-success", timeout=3.33)

with SB(uc=True, test=True) as sb:
    except Exception:
    sb.post_message("Selenium wasn't detected!", duration=3)

👤 Here are some examples that use UC Mode

👤 Here are some UC Mode examples where clicking is required

👤 Here are driver-specific methods added by SeleniumBase for UC Mode: --uc / uc=True



driver.uc_open_with_reconnect(url, reconnect_time=None)


    selector, by="css selector",
    timeout=settings.SMALL_TIMEOUT, reconnect_time=None)


(Note that the reconnect_time is used to specify how long the driver should be disconnected from Chrome to prevent detection before reconnecting again.)

👤 Since driver.get(url) is slower in UC Mode for bypassing detection, use driver.default_get(url) for a standard page load instead:

driver.default_get(url)  # Faster, but Selenium can be detected

👤 Here are some examples of using those special UC Mode methods: (Use self.driver for BaseCase formats. Use sb.driver for SB() formats):

driver.uc_open_with_reconnect("", reconnect_time=5)
driver.uc_open_with_reconnect("", 5)


👤 You can also set the reconnect_time / timeout to "breakpoint" as a valid option. This allows the user to perform manual actions (until typing c and pressing ENTER to continue from the breakpoint):

driver.uc_open_with_reconnect("", reconnect_time="breakpoint")
driver.uc_open_with_reconnect("", "breakpoint")


(Note that while the special UC Mode breakpoint is active, you can't issue Selenium commands to the browser, and the browser can't detect Selenium.)

👤 The two main causes of getting detected in UC Mode (which are both easily handled) are: * Timing. (UC Mode methods let you customize default values that aren't good enough for your environment.) * Not using driver.uc_click(selector) when you need to remain undetected while clicking something.

👤 To find out if UC Mode will work at all on a specific site (before adjusting for timing), load your site with the following script:

from seleniumbase import SB

with SB(uc=True) as sb:
    sb.driver.uc_open_with_reconnect(URL, reconnect_time="breakpoint")

(If you remain undetected while loading the page and performing manual actions, then you know you can create a working script once you swap the breakpoint with a time, and add special methods like uc_click as needed.)