E.

I think i have figured those out by now.
And also, no special options to boot prompt are necessary except maybe keyboard settings when using desktop live image.
But maybe that one is not meant for installing.

It is also a good idea to throw those memory cards and sticks into garbage bin and use optical discs and drives instead.

E2. that shop offered to diagnose that Fujitsu for a reasonable amount of money. But it is unclear how much resources it would take to actually fix it. Or is it possible to fix. So the path of least action seemed to be to buy a another machine.

Edit. As you may already know, F2 after  powerbutton should result a box where you could enter the firmware's admin passwd. After entering the right passwd there should be that configuration menu.
And F12 after powerbutton should give the boot menu, after entering the right hdd passwd.
But there's only a dark gray screen, barely noticeble difference from from completely black screen.

Don't have a support contract  with Fujitsu so i should go through that shop. But they couldn't say how much time and money it would take to fix that machine.
(Or if it is possible to fix or not.)

if it is a backlight failure then using an external monitor might be an answer depending on your particular usage.

keep us posted on your progress!

Right after pushing powerbutton, F2 results in a beep and the screen goes from black ro dark gray. So the machine has noticed that i have pushed a key bot nothing else happens after that.
And F12 right after powerbutton results to a beep and dark gray screen also.

The next step would be to send that machine back to that shop. And it would take yet-to.-be-determined amount of money and time.
I'm between sixes and sevens, should i  sent that machine back or not.

On the other hand, that old laptop will cease to work some day.

https://forum.ts.fujitsu.com/forum/viewtopic.php?p=153314

if all else fails, you may want to see if you can get an original set of recovery media and attempt to do whatever methods and/or procedures are required for when recovering from a _factory-stock-original_ machine has a complete hard-drive failure.

please keep us posted on your efforts and hopefully success!

also wanted to update this post to advise that these Fujitsu webpages work for me as of the time of this post:

https://www.fujitsu.com/us/support/products/computing/server-storage/
https://support.ts.fujitsu.com/index.asp?ld=us

edited to ease readability.

Found out the Hard Way that is not a proper way to enforce booting from optical disk.
It doesn't matter if that ssd is connected or not.

Now Lord Anubis is in need for a new host.

It would be easy if i could just make that machine somehow forget that it is supposed to access ssd before booting from optical.
But the first attempts at that have not been successful.

Did you try to reset the BIOS/(U)EFI settings to system default?
There should be a menu somewhere saying something like "load save defaults".

I never do advanced installs and I never have your problem. Although, its possible I am missing something.

And then there were the 3rd mistake. Not quite sure if i can get to configuration_menu or boot_menu after that.
It would be easy if i could just make that machine somehow forget that it is supposed to access ssd before booting from optical.
But the first attempts at that have not been successful.

EFI might have been too, but UEFI is way more vulnerable.

Sad to say, but corporations be dumbasses.

And noticed that cannot boot from usb-dvd-drive if that ssd is disconnected.
It may have been a mistake to set that disk passwd. I suspect it to be the cause that firmware needs ssd before booting from optical.

In boot order optical is before ssd, but not the absolutely first, i think. Have to confirm if i get a chance.

E. Firmware version is 1.28 . The date of it is from december of 2022, i think. Suspect that date is when the firmware was updated, not the date when fujitsu published it.

I'm worried that i have to re-install windows to Fujitsu so that i can get a proper EFI-partition back. Yuck.

Using w10 or ubuntu install disk is not necessary. Running grub-install with right parameters is enough as it should be.
Could also bypass reading /boot/efi/something/grub.cfg before going to /boot.

It will be highly practical if it is only vmlinuz that needs to be signed (or verified during boot process).
On the other hand maybe initrd should be signed also.

Edit. question: can i brick my machine by experimenting with mokutil?
I think that PK and KEK should be left alone even if they can be changed.

Edit. I have already tried ctr+alt+del, ctrl+alt+backspace. Didn't seem to do anything. Maybe i'll try again but somewhat i doubt that they help.