環境：
1、ubuntu系統
2、selenium 3.141.0
3、火狐瀏覽器驅動 geckodriver-v0.24.0-linux32
在Python中執行腳本：
from selenium import webdriver
browser = webdriver.Firefox()
結果提示：Message: Unable to find a matching set of capabilities
Traceback (most recent call last):
File "/home/yanner/seleniumtest/sousuo.py", line 2, in <module>
browser = webdriver.Firefox()
File "/usr/local/lib/python2.7/dist-packages/selenium/webdriver/firefox/webdriver.py", line 174, in __init__
keep_alive=True)
File "/usr/local/lib/python2.7/dist-packages/selenium/webdriver/remote/webdriver.py", line 157, in __init__
self.start_session(capabilities, browser_profile)
File "/usr/local/lib/python2.7/dist-packages/selenium/webdriver/remote/webdriver.py", line 252, in start_session
response = self.execute(Command.NEW_SESSION, parameters)
File "/usr/local/lib/python2.7/dist-packages/selenium/webdriver/remote/webdriver.py", line 321, in execute
self.error_handler.check_response(response)
File "/usr/local/lib/python2.7/dist-packages/selenium/webdriver/remote/errorhandler.py", line 242, in check_response
raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.SessionNotCreatedException: Message: Unable to find a matching set of capabilities
解決方法：更新firefox瀏覽器
1、從瀏覽器進入firefox官網下載最新版本firefox-67.0.4.tar.bz2
2、進入下載目錄，將該文件解壓。
3、打開終端模擬器，進入到下載目錄，輸入安裝命令行。
root@yanner-VirtualBox:/home/yanner/下載/firefox# sudo apt-get install firefox
更新后，Firefox 52.0.2
再次執行腳本，正常打開瀏覽器：
from selenium import webdriver
browser = webdriver.Firefox()
但是，打開網頁失敗，提示Message: connection refused：
from selenium import webdriver
browser = webdriver.Firefox()
browser.get("http://www.baidu.com")
browser.find_element_by_id("kw").send_keys("selenium")
browser.find_element_by_id("su").click()
browser.quit()
研究了半天，將驅動geckodriver-v0.24.0-linux32降版本，將目錄/usr/local/bin下的驅動geckodriver刪掉，下載了geckodriver-v0.17.0-linux32解壓復制到/usr/local/bin下（可以參考上一篇文章https://www.cnblogs.com/yanner/p/11077762.html），
再次運行上面的腳本，正常打開！