The Minecraft Grub Theme Trio:

Minecraft Main Menu	Minecraft World Selection Menu	> Using both themes together <

• ADDITIONALLY!: Check out this minecraft plymouth theme by nikp123 for a minecraft loading screen during boot: https://github.com/nikp123/minecraft-plymouth-theme

The REAL minecraft experience when booting your system!

This is a guide on how you can have two grub menus after one another, each in a different theme!

I made this so I can use my minegrub theme that looks like the Minecraft main menu to enter my second minegrub theme that looks like the minecraft world selection menu just like in the real game

Yea, its possible, and its fun

minegrub-double-menu-preview.mp4

Installation

• Install your two themes, in this case:

  git clone https://github.com/Lxtharia/minegrub-world-sel-theme.git && cd minegrub-world-sel-theme
  sudo cp -ruv minegrub-world-selection /boot/grub/themes/
  
  cd ..
  ### And the other one
  git clone https://github.com/Lxtharia/minegrub-theme.git && cd minegrub-theme
  sudo cp -ruv minegrub /boot/grub/themes/

  • Check them out here for more instructions: minegrub-theme and minegrub-world-sel-theme

• Set the world-selection theme in /etc/default/grub and other trivial stuff

  GRUB_TIMEOUT_STYLE=menu
  ...
  GRUB_THEME=/boot/grub/themes/minegrub-world-selection/theme.txt
  ...
  GRUB_GFXMODE=...

• clone this repo or download the files (it's only two)

  git clone https://github.com/Lxtharia/minegrub-double-menu.git && cd minegrub-double-menu

• copy the files

  sudo cp ./mainmenu.cfg /boot/grub/
  sudo cp ./05_twomenus /etc/grub.d/
  chmod +x /etc/grub.d/05_twomenus

• regenerate the grub.cfg

  sudo grub-mkconfig -o /boot/grub/grub.cfg

• to enable it, you need to set a grub environmental variable:

  sudo grub-editenv - set config_file=mainmenu.cfg

• Done!

• If you want to disable it all you need to do is

  sudo grub-editenv - unset config_file

Ventoy Support

Ventoy is using a modified version of grub, but has theme support. If you want Ventoy to use both themes see here.

Explanation (???)

oh boi here we go:

We have our cool theme to select our distro, but now we want a main menu "before it".

When grub starts, it by default reads the file grub.cfg usually located in /boot/grub/grub.cfg to set all the options (like timeout, default boot option, theme) and add all the boot options. This file is usually generated by grub-mkconfig which uses configuration options set in /etc/default/grub and scripts in /etc/grub.d/* to create the full config file.

NOW: what do we need?

We want grub to read a second .cfg file that sets the theme to the main menu theme (./mainmenu.cfg) and that includes boot options like "Singlebooter" "Onlinebooter" or "UEFI Realms" (so cool). And if we select "Singlebooter" we want to load "the real config file" with the world-selection theme and that includes all of your personal boot options.

• We need some code to autoload another config file

• To get the code that does that into grub.cfg we write it in a file (05_twomenus) and put it in /etc/grub.d/, so it gets included when generating the grub.cfg

• To automatically load another configfile we can just call configfile $prefix/mainmenu.cfg in grub.cfg

  • $prefix contains the disk/partition absolute path to your /boot/grub folder

• For some reason I thought it was a good idea to turn it off easily:

  • We only load the main-menu if the environmental variable config_file= is set
  • if yes, we load that file (with configfile $prefix/$config_file)
  • grub.cfg normally loads variables automatically from the file /boot/grub/grubenv, so all we have to do is set it there
  • with grub-editenv - set config_file=mainmenu.cfg

• now mainmenu.cfg gets loaded.

• the first boot item will load our grub.cfg-configfile again.

• BUT:

• to prevent grub.cfg to load the other config file again, we put that code into another if clause

• when we select an item, grub sets the variable chosen, so we can only load the config file if this variable has not been set yet

• and that's it!

TLDR:

• grub.cfg tries to load a second config_file if the grub environmental variable config_file is set
• this config file shows us the main menu
• if we select "Singlebooter" it loads the grub.cfg again
• but now the "chosen" variable is set (because we have chosen an option)
• and if this variable is set, we prevent the grub.cfg to load mainmenu.cfg, and we see our normal boot options

Notes (!!!)

• the fun zone

• I write unnesessarily long READMEs

• you don't have to READ IT, but you did read (until) this line, so: Hello :D

• Fun-fact: if you generate or copy your grub.cfg to /boot/grub/custom.cfg your grub will be stuck in an infinite loop! (Luckily I learned that in a VM)

• I'm proud of this

• USE THIS ON YOUR OWN RISK, if your grub is broken i take no responsibilty, better have that live boot stick ready