a new idempier install constantly logs out of the sessions, it turns out it's a bug and you could try the following workaround:
root@do-idempiere:/opt/idempiere-server/log# vim /opt/idempiere-server/jettyhome/work/jetty-0_0_0_0-8443-org_adempiere_ui_zk_8_2_0_202112110706_jar-_webui-any-/webapp/web/js/jawwa/atmosphere/serverpush.js
I added 2==1 to make the if fail and avoid the timeout.
if (textStatus != "timeout" && textStatus != "abort" && errorThrown != "SessionNotFound" && jqxhr.status != 504 && 2 == 1) {