[keycloak-user] "You took too long to login" after first login request after SSO session idle occurs (NOT login timeout)

[Jordan Keith]

We have set the SSO Session Idle to 13 minutes to match our access token lifespace of 15 minutes in order to workaround the fact that browsers may not delete session cookies. This has caused another issue, whereby the user receives the error "You took too long to login. Login process starting from beginning" even when they spend no time waiting on the login screen in a certain scenario. Here's the scenario: 

1). Log into application. 
2). Close browser tab containing application. 
3). Wait 15 minutes (SSO idle + 2 minute grace period) 
4). Open application again. You'll be directed to the login page by keycloak. 
5). Attempt to login and receive the error "You took too long to login. Login process starting from beginning." 

Why do I receive this error even when I attempt to login immediately after opening the log in page?