Upate from 4.4.9 to 5.0

I’m trying to update it to 5.0-7 from 4.4.9 and getting some errors. Can someone advise on how to clear these errors? Thanks.

The system can not be updated to UCS 5.0 due to the following reasons:

WARNING: The following packages from UCS-4 are still installed, which are no longer supported with UCS-5:
univention-kde Mark KDE as manually installed “apt-mark manual
kde-standard” to keep KDE
univention-mozilla-firefox univention-x-core

Use “univention-remove --purge” with the packages as following arguments to remove them

The following hosts must be upgraded to UCS 4.4-8 first:
cn=ucs01, cn=dc, cn=computers,dc=curiosity,dc=intranet: 4.4-0