F29 System Wide Change: Hide the grub menu

[Jan Kurik]

= Proposed System Wide Change: Hide the grub menu =
https://fedoraproject.org/wiki/Changes/HiddenGrubMenu

Owner(s):
  * Hans de Goede <hdegoede at redhat dot com>

On systems with only a single OS installed, the grub menu does not
offer any useful functionality, so we should hide it by default.

== Detailed description ==
On systems with only a single OS installed, the grub menu's only
function is to allow booting older kernels, which is only necessary as
a rescue option in case of a severe kernel bug and as such not
something which is directly useful for normal use.
Fedora already has a lot of work done to not show too technical boot
messages to end users during bootup, e.g. we pass quiet to the kernel
and we've plymouth to show a bootsplash instead of a bunch of
"Starting service-foo: OK" messages.
The grub menu with its kernel versions is another example of showing
too technical info to end-users and on non multi-boot systems it
normally is not necessary, so it is better to hide it.
The implementation of this consists of the following changes:
1. Currently if the menu is hidden the user needs to press ESC to show
it, modify grub to also except F8 as show-menu key, there are 2
reasons for this:
1.1 F8 is (was) the key to bring up the boot/rescue menu in Windows
1.2 On some machines ESC brings up the firmware-setup menu
2. On non multi-boot systems set GRUB_HIDDEN_TIMEOUT=1 and
GRUB_HIDDEN_TIMEOUT_QUIET="true" in /etc/default/grub

== Scope ==
* Proposal owners:
1. Add patches to grub to also make pressing F8 show the menu
2. Make sure this is all properly documented in release-notes, etc.
3. Write patches for anaconda to set GRUB_HIDDEN_TIMEOUT=1 and
GRUB_HIDDEN_TIMEOUT_QUIET="true" in /etc/default/grub on non
multi-boot systems

* Other developers:
The anaconda developers will need to review and merge the
/etc/default/grub related patches

* Release engineering:
https://pagure.io/releng/issue/7539

** List of deliverables: all

* Policies and guidelines:
The policies and guidelines do not need to be updated.

* Trademark approval:
Not needed for this Change.