Editing grub boot menu, how to save?

[Bo Berglund]

I have found this webpage describing how to edit a grub boot menu item, but it
does not work...
https://docs.oracle.com/cd/E19120-01/open.solaris/819-2379/fwbme/index.html

What happens is this:
- On the boot menu I select a line I want to edit.
- Then I hit the letter e on the keyboard and the edit starts
- I move the cursor to where I will add text and type away
- Now I want to save the edit but *there is no save cmd*!!!

The help line at the bottom has other explanations like TAB for completion and
Ctrl-x or F10 to reboot and ESC to return while discarding edits.

But nowhere is there a way to actually *save* the edited menu entry!

I just want to change the label so that it is unmistakable *what* is going to
boot by that line.
Currently my top line only says "Ubuntu" and since there are multiple Ubuntus
this is not very user friendly!

The help text says at the beginning that this is an  Emacs like environment, but
I have never ever used Emacs so if there is a specific "commonly known" key
combination to save the edit, I do not know it.

Googling "Emacs save command" says that Ctrl-x followed by Ctrl-s will save the
work, but in this case Ctrl-x will actually exit without saving and continue the
boot operation instead!

Any ideas?


-- 
Bo Berglund
Developer in Sweden