I have been using selenium for automatic browser simulations and web scraping in python and it has worked well for me. But now, I have to run it behind a proxy server. So no
You need to set desired capabilities or browser profile, like this:
profile = webdriver.FirefoxProfile()
profile.set_preference("network.proxy.type", 1)
profile.set_preference("network.proxy.http", "proxy.server.address")
profile.set_preference("network.proxy.http_port", "port_number")
profile.update_preferences()
driver = webdriver.Firefox(firefox_profile=profile)
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