class Capybara::Server

def responsive?
  return false if @server_thread&.join(0)
  res = @checker.request { |http| http.get('/__identify__') }
  if res.is_a?(Net::HTTPSuccess) || res.is_a?(Net::HTTPRedirection)
    return res.body == app.object_id.to_s
  end
rescue SystemCallError, Net::ReadTimeout, OpenSSL::SSL::SSLError
  false
end