I am trying to install the latest virtualbox - I’ve tried installing the .rpm (using both “install software” and “rpm”) and using the .run file - I keep getting the message:
“The system is not currently set up to build kernel modules.”
It wants the linux kernel header files.
This seems normal and easily handled, I’ve tried installing from YaST/Software/patterns, all the “devel” patterns and searching for “kernel headers” etc. But for some reason this isn’t working. I can’t seem to find kernel-headers-default in the 15.0 repos - I guess they’ve renamed this (but I thought the “devel” patterns would find whatever it’s currently called).
kernel-devel contains the headers you can’t develop without them. Headers are no longer packed separately.
thanks, g 
… is it the “vanilla” kernel I should be using? I never saw such a name before. …used to be called “default” and “kmp”
I wonder, then, what the issue with vbox is?
What you probably need, is “kernel-default-devel”. That should be pulled in by “kernel-devel”, assuming that you are using “kernel-default”. Or, at least, that’s what happen here.
development should match the flavor of your installed kernel
https://pkgs.org/download/kernel-headers
https://opensuse.pkgs.org/15.2/opensuse-oss-x86_64/linux-glibc-devel-5.3-lp152.1.1.x86_64.rpm.html
No need to install nearly a gigabyte of kernel-source!
linux-glibc-devel will be your friend 
zypper if linux-glibc-devel
Repository ‘KDE-Extra’ is out-of-date. You can run ‘zypper refresh’ as root to update it.
Loading repository data…
Reading installed packages…Information for package linux-glibc-devel:
Repository : OSS
Name : linux-glibc-devel
Version : 5.3-lp152.1.1
Arch : x86_64
Vendor : openSUSE
Installed Size : 4,4 MiB
Installed : Yes (automatically)
Status : up-to-date
Source package : linux-glibc-devel-5.3-lp152.1.1.src
Summary : Linux headers for userspace development
Description :
This package provides Linux kernel headers, the kernel API description
required for compilation of almost all programs. This is the userspace
interface; compiling external kernel modules requires
kernel-(flavor)-devel, or kernel-syms to pull in all kernel-*-devel,
packages, instead.
qed
You need kernel-devel
No, it is not what description you quoted says.