Hello Pascal
Thank you very much for help with commands.
Yes, you have true. If is my interpretation of outputs of commands correct, main of Ubuntu based distribution use subvolumes. Only Ubuntu Desktop not use subvolumes. Only Ubuntu Desktop finds os-prober correct.
It is very valuable information for developers, how to repair this bug.
More information on screenshots on this link
Other my tests:
I installed more distributions on the same SSD on ext4 on the same PC. All work correct. On every last installed distribution are automatically displayed previous installed distributions in GRUB. On BTRFS no.
Source of issue are BTRFS subvolumes.
______________________________________________________________
> Od: "Pascal Hambourg" <pascal@plouf.fr.eu.org>
> Komu: "Matej Marko" <ekonom1@atlas.sk>
> Dátum: 15.02.2025 13:09
> Predmet: Re: os-prober issue. Not find all distributions on multi boot SSD
>
> CC: <debian-boot@lists.debian.org>
On 15/02/2025 at 10:09, Matej Marko wrote: