makemkvcon 2.0.0 (Linux, Flathub) segfaults when opening any Blu-ray from files (ISO or folder). Physical discs and DVD ISOs are fine
After the Flathub package updated from 1.18.4 to 2.0.0 (commit 1aa1825c), makemkvcon crashes with a segmentation fault (exit code 139) whenever it opens a Blu-ray from files. This happens with makemkvcon -r --noscan --minlength=0 info iso:/path/disc.iso on every Blu-ray ISO I tried, and with info file:/path/folder on an extracted Blu-ray folder. It dies about a second after starting, without printing an error. The last messages are "Using direct disc access mode" for an ISO, or "Opening files on harddrive" followed by "AACS directory not present, assuming unencrypted disc" for a folder. The flags don't matter (with or without -r, --noscan, --minlength), and --debug=<file> doesn't write a log before the crash. The sources are decrypted backups made with makemkvcon backup --decrypt. A folder written by 2.0.0's own backup crashes too, so it isn't limited to backups made with older versions. Removing the MAKEMKV/ metadata directory from the backup doesn't help either.
On the same system, these work normally: info disc:99 drive scans, info dev: on physical BD, UHD and DVD discs (LibreDrive), info iso: on DVD ISOs, and backup --decrypt disc:N from a physical Blu-ray (I only ran it partway, but it produced decrypted, playable streams). Rolling back to 1.18.4 (flatpak update --commit=ba1b0921…) fixes it: the same ISOs open fine and give the same title list as before.
Environment: Debian 13, kernel 6.12, Flathub com.makemkv.MakeMKV (KDE 5.15-25.08 runtime), LG WH16NS60 and ASUS BW-16D1HT drives. I only tested makemkvcon, not the GUI.