Dear Maintainer, I'd love to get a BOOTLOADER_ID config option too. My use case is to install multiple debian versions in parallel, including their own grub version.
This can be useful when upgrading a remote system (without remote console) from say debian12 to debian13 with minimal risk and minimal downtime: There could be two distinct partitions for /boot and / Debian12 uses one set of those partitions, debian13 the other. When the debian13 install is done, use "efibootmgr --bootnext" to boot into debian13 and reboot. In case this fails to boot, a watchdog (or human) can powercycle the system and it will boot into debian12 again. Otherwise if the new system works, use "efibootmgr --bootorder" to change the order permanently. My current workaround is to configure apt (DPkg::Path) to include /usr/local/sbin which contains a simple wrapper script for grub-install that appends to --bootloader-id=xxxx param. Thanks Jörn
