I would like to that the gui installer execute grub-install with additional --removable --no-nvram flags.
Is this possible? Or can I simple wait until the installation failed and run grub-install manual?
Manjaro version: 21.2.2 Cinnamon
Interesting topic so I tried in a vm and found some equally interesting stuff. The installation file you see on the desktop in live environment is located in /usr/share/applications/calamares.desktop which executes /usr/bin/calamares_polkit %f which is just a bash script:
#!/bin/bash
sudo -E /usr/bin/calamares "$@"
Now calamares launches and reads the configuration files from /etc/calamares. Go to the modules directory and change grubInstall parameter from grub-install to grub-install --removable --no-nvram in bootloader.conf file. This command will do it for you:
cd /etc/calamares/modules
sudo sed -i 's/grub-install/grub-install --removable --no-nvram/g' bootloader.conf
cat bootloader.conf #to ensure that the changes take place
Note: I have not tried this on real hardware but it works in a KDE manjaro virtual machine so if you are certain that the normal method will fail then you can give this a try and share if it works.
Thanks for the fast answer. I will try this.
Sadly both methods does not work.
After modifying the bootloader.conf grub does exit with 127.
Running grub manual does also not work. I had use --boot-directory= as described at the arch wiki. Grub says that no error has occurred. But after a restart, I did only get a grub shell and was not able to boot manjaro.