This setting applies to all users in your organization.
1

From the customer view in https://admin.webex.com, go to Settings and scroll down to the Authentication section.

2

Toggle the switch under Remember Me Controls to on.

3

Set the number of days before users have to reenter their email address.

The browser sets a cookie, containing the hashed email address, to expire at the end of the configured period.

Users can clear their Webex browser cookies if they want to sign in with a different email address.