auto login user settings ;please explain what these setting mean.

It is not clear to me what these setting mean !

Guidance appreciated.

If it is set to RED what happens ?

If it is set to gray what happens ?

  RED oval set to right

Email Auto-loginDisabling email auto-login allows you to forward our emails to anyone you wish without concern they can access your account. Even when email auto-login is enabled, we protect sensitive parts of your account.

‘gray setting to left

Email Auto-loginEnabling email auto-login signs you in from links in Seeking Alpha emails. Forwarding emails will give others limited access to your account. Even when email auto-login is enabled, we protect sensitive parts of your account.