带冒号的Capybara app_host不能使用Firefox

Question

我对一些水豚/硒测试有一个非常奇怪的问题。对于上下文，我用硒和水豚来运行ruby-rspec。我在Chrome上运行它时测试工作正常，但由于某些原因，使用Firefox，第二个URL失败。

spec_helper.rb

BROWSER = :chrome
BROWSER = :firefox

Capybara.register_driver :selenium do |app|
  Capybara::Selenium::Driver.new(app, browser: BROWSER)
end

Capybara.default_driver = :selenium
# This one works
Capybara.app_host = "https://bar.foo.com/home"
# This one doesn't
Capybara.app_host = "https://foo.bar.com:18661/home"

我得到的错误：

Selenium::WebDriver::Error::WebDriverError: 
WebDriverError@chrome://marionette/content/error.js:172:5
InsecureCertificateError@chrome://marionette/content/error.js:291:5
handleReadyState@chrome://marionette/content/listener.js:274:21
handleEvent@chrome://marionette/content/listener.js:247:9