But instead it looks a bit more complicated, specially because of how to handle Packman repository there, and what to do with huge backup made by the upgrade process.
With upcoming 15.7, which is the most recommended method to upgrade, offline or still online?
It is not recommendable to upgrade your openSUSE Leap 15.x with a running Wayland- or X11-session! Stop your graphical login manager KDM/GDM/what else, before you start the os upgrade.
If you want that your (open-)SUSE Linux still receive security updates in 2026 you must change to Leap 16.0 (or to an other linux distribution) or you pay money for a SUSE Linux Enterprise Desktop standard subscription (SLED 15 SP7). https://forums.opensuse.org/t/so-slooowwwroolll-questions/180878/15
But, please, please, be aware that, especially for KDE Plasma systems, the upcoming Leap 15.6 to Leap 16.0 upgrade will be a major KDE Plasma version change – Qt5 → Qt 6 and, KDE Plasma 5 → KDE Plasma 6.
Upgrade the base system – use only the openSUSE Leap 16.0 base system repositories.
Afterwards, add the needed Packman repositories but, only to work around licensing issues.
Migrate your user’s directories to KDE Plasma 6 – the KDE applications will be at the newest supportable version anyway … «Major action point – KDE PIM … »
Add any KDE:Extra repositories as needed for the KDE Plasma applications which aren’t included in the Leap 16.0 base system repositories.
Ensure that, you don’t have any KDE Plasma 5 / Qt 5 applications left on the system after the upgrade has completed – execute the following verification commands:
It’s a good idea to also perform the above mentioned “verify” and “package” checks before you begin the upgrade.
For each package listed in “–system”, “–unneeded” and “–orphaned” execute a “zypper search” for the basic package name – the name without any version numbers …
For each package listed in “–system”, “–unneeded” and “–orphaned” execute –
# zypper remove --clean-deps «package name with Plasma 5 version»
** provided that you aren’t breaking any KDE Plasma 6 / Qt 6 dependencies. **
If the upgrade “housekeeping” breaks the KDE Plasma 6 / Qt 6 dependencies then, additional work will be needed to ensure that, the correct package list has been installed.
Then, it may be somewhat easier – AFAIK, neither GNOME nor XFCE will undergo a major version upgrade with Leap 16 – but,
the basic rule remains – first upgrade using only the openSUSE Leap 16.0 base system repositories, and then –
Add the needed Packman Leap 16.0 repositories and, begin including the Packman packages you need.
And, because you depend heavily on the Packman versions, you’ll still need to use the “zypper packages --???” commands, to clean out all the remaining Leap 15.6 Packman packages, after you’ve installed the corresponding Leap 16.0 Packman packages.