这个错误讯息…

selenium.common.exceptions.WebDriverException: Message: unknown error: ChromeDriver only supports characters in the BMP

…暗示ChromeDriver无法 通过方法发送表情符号信号。
send_keys()

ChromeDriver仅支持BMP中的字符，这是Chromium团队的一个已知问题，因为ChromeDriver仍不支持 Unicode字符。因此，它是无法发送任何字符以外通过ChromeDriver。结果，任何发送SMP字符（例如CJK，Emojis，Symbols等）的尝试都会引发错误。

Alternative

一个潜在的替代方法是使用_GeckoDriver_ / Firefox.

• Code Block:

  from selenium import webdriver
  

  from selenium.webdriver.support.ui import WebDriverWait
  from selenium.webdriver.common.by import By
  from selenium.webdriver.support import expected_conditions as EC

  driver = webdriver.Firefox(executable_path=r’C:\Utility\BrowserDrivers\geckodriver.exe’)
  driver.get('https://www.google.com/’)

  Chineese Character

  WebDriverWait(driver, 20).until(EC.element_to_be_clickable((By.NAME, “q”))).send_keys(“𠀀”)

  Emoji Character

  WebDriverWait(driver, 20).until(EC.element_to_be_clickable((By.NAME, “q”))).send_keys(“💩”)

• Browser Snapshot:

You can find a relevant discussion in OpenQA.Selenium.WebDriverException:
‘unknown error: ChromeDriver only supports characters in the BMP while sending
an emoji through C#
Selenium

Reference

Issue 2269: Impossible to add special characters with a unicode after
FFFF