DX APM GUI is not automatically logout if no work happens, it logouts after some time (30 min) if users are not using or working.
Release : 20.2
Component : Introscope
Because APM continuously polls, the dxisession is actively being used and thus the 30 minute timeout for other areas of DXI does not apply. There is no configuration option to change this, as the polling logic is core to the APM solution.
It can be considered "Working as Designed' for the APM case that the dxisession timeouts are not enforced, as the token is continually being refreshed.
When navigating from Launch Pad to Settings, since DXI is a single-page application the display of Settings page does not incur a backend request. Thus no timeout occurs. Selecting one of the other panels (such as Users), it does issue a backend request and will return a 401 Unauthorized error.
A test of leaving the browser on LaunchPad for an hour and then navigating to Settings->Users. As mentioned before, the Settings page does not incur a backend call so is displayed without any network traffic. Clicking on Users does perform a backend call and in the SaaS cloud management, it recognizes that the token has expired and redirects to the sppclient/ login page.
A similar action should be happening for on-prem when the token has expired, but if you are not seeing this then that implementation has an issue. With merging of the SaaS/on-prem should help to resolve this for both environments in a yet to be determined future release.