I migrated from Tumbleweed to Slowroll using the openSUSE Migration Tool from GitHub. After restarting, I configured the repositories according to the Slowroll wiki:
Removed the old Packman repository
Added the Slowroll Essentials Packman repository using (link from wiki):
sudo zypper ar --refresh -p 70 http://ftp.gwdg.de/pub/linux/misc/packman/suse/openSUSE_Slowroll/Essentials/ packman
Well, when I run sudo zypper dup, the migration tool appears to have missed some graphics packages. The distribution upgrade is asking me to downgrade Mesa and related graphics libraries to older Slowroll versions:
Computing distribution upgrade...
9 Problems:
Problem: 1: problem with the installed Mesa-26.0.1-1699.2.pm.1.x86_64
Problem: 2: problem with the installed Mesa-dri-26.0.1-1699.2.pm.1.x86_64
Problem: 3: problem with the installed Mesa-libEGL1-26.0.1-1699.2.pm.1.x86_64
Problem: 4: problem with the installed Mesa-libGL1-26.0.1-1699.2.pm.1.x86_64
Problem: 5: problem with the installed Mesa-libva-26.0.1-1699.2.pm.1.x86_64
Problem: 6: problem with the installed Mesa-vulkan-device-select-26.0.1-1699.2.pm.1.x86_64
Problem: 7: problem with the installed libgbm1-26.0.1-1699.2.pm.1.x86_64
Problem: 8: problem with the installed libvulkan_lvp-26.0.1-1699.2.pm.1.x86_64
Problem: 9: problem with the installed libvulkan_radeon-26.0.1-1699.2.pm.1.x86_64
Solution 1: install Mesa-25.3.4-1.1.x86_64 from vendor openSUSE
replacing Mesa-26.0.1-1699.2.pm.1.x86_64 from vendor http://packman.links2linux.de
Solution 2: keep obsolete Mesa-26.0.1-1699.2.pm.1.x86_64
Finally my question: Should I proceed with the downgrade to Mesa 25.3.4 from Slowroll, or should I keep the newer package versions and wait for Slowroll to catch up?
Assuming that the repo addresses are correct (as @knurpht is asking), Packman Essentials does not provide Mesa, so the only update candidate the system finds is the OSS one.
Likely you installed Mesa from the Packman Extra repo.
Yes I did install everything two weeks ago at that time I had Tumbleweed. While migrating to Slowroll the tool also asked me to deactivate the packman repo. So after the migration was complete I removed that repo entirely and added the recommended (in Slowroll wiki) sudo zypper ar --refresh -p 70 http://ftp.gwdg.de/pub/linux/misc/packman/suse/openSUSE_Slowroll/Essentials/ packman.
Your repos look OK. The only reason to have Mesa from Packman is having an ancient AMD GPU that needs HW video decoding; if that is not your case I would avoid the Packman Mesa since it is likely to cause mismatches every now and then with nothing else to gain and with only the “Essentials” from Packman Slowroll will never “catch up” with that.
So I would advise to “downgrade” to the OSS Mesa and related libraries and enjoy.
I have a Ryzen HX 370 with an 890M, so the opposite of ancient AMD GPU. I will downgrade, just noticed there are some options that are not described d / ? = delete / help ?
Problem: 1: problem with the installed Mesa-26.0.1-1699.2.pm.1.x86_64
Solution 1: install Mesa-25.3.4-1.1.x86_64 from vendor openSUSE
replacing Mesa-26.0.1-1699.2.pm.1.x86_64 from vendor http://packman.links2linux.de
Solution 2: keep obsolete Mesa-26.0.1-1699.2.pm.1.x86_64
Choose from above solutions by number or skip, retry or cancel [1/2/s/r/c/d/?] (c):
d for “details” as you can see by typing “?”:
Choose from above solutions by number or cancel [1/2/c/d/?] (c): ?
#1 : 1 - Choose solution 1
#2 : 2 - Choose solution 2
#3 : c - Choose no solution and cancel.
#4 : d - Toggle show detailed conflict information.