To change application timeout:
set applications application junos-ssh inactivity-timeout 1440
set applications application junos-telnet inactivity-timeout 1440
set system services web-management session idle-timeout 1440
Note: auto complete does not work after application, so you will have to type it all in.
To view timeout settings, exit to cli
start shell user root
show usp app-def tcp
And you’re done.