Is there a way to force logout of a user after predefined idle time?
It depends what you need/want. There is a session timeout on php level you can use, but it will not automatically turn your screen into the login screen. A trick might be to use a javascript timer with a redirect in the header. Other option is to use a dashboard application as you can set a timer there to refresh the form which can be used to force a thing like this.
Thank you for the possible options.
Being forced to create measures myself, I can visualize a further method: A timeout counter in the login table, that is consulted at the beginning of each application. Excess idle time redirects to login screen
That might work or not. If the idle time is too long php might have quit already. If you check on each application you expect the user to return within the time of the php session…