A few hour ago I decided to reinstall opensuse tumbleweed. The installation is ok, I did not mess with efi partition, just asked opensuse to install /boot/efi, and that's it.
When I boot again on the grub, windows disappear, so I went on my quest to try to restore windows in the grub. osprobe or grub2-mkconfig do not work, they can't seem to locate windows.
So I finally choose to manually add windows in my grub (40_custom), but after a few try, I have the error "signature invalid", so I reinstall opensuse, but this time unchecking 'trusted boot'. Nothing change.
After a few research on google, I find rEFInd, a utility that should have helped me. After installing it, it could not finish the change in the efi partition, and now when trying to boot windows, it just display a still background (the rEFInd background), and do nothing.
Then I try to boot on opensuse, but all menuentry are broken ! So I reinstall again opensuse and try this time to obtain a windows iso to burn on my usb thumb stick to boot, repair the EFI, nuke opensuse (I have work to do on windows, I will go back on Opensuse later).
After download the image from microsoft in my language, I burn it with the tool provided by opensuse : 'Disk Image Writer'. It is burn on /dev/sdb (which was a fat partition).
When I restart my computer I go in the boot option, select the usb (only EFI is proposed) and black screen and reboot happen.
I would like to repair the EFI partition to boot on windows, I have the usb stick with windows 10 on it, can not boot, if anyone has an answer I take it.
Right now the only thing I can do, is to go inside the boot option (via bios), select a partition to boot (since the grub is still broken by rEFInd).