GuardAuthenticatorInterface::supportsRememberMe()

Does this method support remember me cookies?

Remember me cookie will be set if all of the following are met: A) This method returns true B) The rememberme key under your firewall is configured C) The "remember me" functionality is activated. This is usually done by having a _rememberme checkbox in your form, but can be configured by the "alwaysrememberme" and "remembermeparameter" parameters under the "remember_me" firewall key