The new options timeoutURL and signonURL are available for you to set with SAML authentication in order to be having more control over which URL the users are redirected to when there is a problem.
timeoutURL will be used instead of errorURL in case of time out.
Example: you can use a page stating "You have hit a Time Out"
signonURL will be used instead of errorURL for invalid session.
Example: you can use a page stating "Your Session is not valid"
We recommend setting those up to specific separate pages in order to be able to easily understand what exactly is going on.
Note as with all the Security setup pages in CSA, the pages should be available in browser