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Downgrade from version 4.0 to earlier version is supported to provide rollback capability in case of major issues arise. Downgrades are executed with technical support assistance, not by customers themselves.
Notable changes
Temporary directory has been changed from /var/lib/oneportal/tmp to /tmp with systemd PrivateTmp= enabled. If /var/lib/oneportal/tmp exists after upgrade, it should be removed.
Remove JAVA_TMPDIR and JAVA_HOME variables from /etc/sysconfig/oneportal if they exists after upgrade.
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Improvement
ONEP-2299 Configuration options for after-changePassword behaviour
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ONEP-2324 Drop deprecated authorisation indexes
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