Created attachment 777382 [details]
15.0 y2logs from host ab250

YaST2 currently offers no opportunity to specify a custom name to facilitate
multiboot hosts. It needs one.

Because it does not, e.g. when installation of Leap follows installation of
Tumbleweed, the previous UEFI configuration is destroyed. The BIOS boot manager
may or may not accommodate a proper selection of the preferred choice from the
EFI/ESP partition. In the Leap follows TW case I just tried with an Asus
B250M-C/CSM Kaby Lake motherboard with AMI BIOS version 1205 of 2018-05-11, the
BIOS did not.

As I normally do during installation, I deselected probe foreign OS. In
attempting to avoid this overwrite, during installation of 15.0 I used vi to
edit /mnt/etc/default/grub to include GRUB_DISTRIBUTOR="opensuse150". Actual
bootloader installation at the end of overall installation changed it to
GRUB_DISTRIBUTOR=, with the result that next boot only offered 15.0 to the
exclusion of TW's /boot/grub2/custom.cfg which contains the custom stanzas for
the other installed distros. I was forced to "choose" only 15.0 at next boot. I
did work around that by using e on the 15.0 stanza to specify the TW kernel and
initrd.

Current EFI boot configuration:
# efibootmgr
BootCurrent: 0000
BootOrder: 0000,0001,0002
Boot0000* opensuse
Boot0001* debian
Boot0002* UEFI OS

Expected EFI boot configuration subsequent to 15.0 installation was:
# efibootmgr
BootCurrent: 0000
BootOrder: 0000,0001,0002,0003,0004
Boot0000* opensuseTW
Boot0001* debian
Boot0002* ubuntu
Boot0003* opensuse150
Boot0004* UEFI OS