UPDATE : Also tested with the newest Flatpak version on Linux Mint 22.3 "Zena" with XFCE rather than KDE this time. I did a basic test, I merely tried to open an ISO file with my drive unplugged. Instant crash.
These crashes on Ubuntu Noble and Linux Mint Zena seem to occur regardless of whether you open a UHD ISO or a regular Blu-ray ISO. DVD ISOs, on the other hand, seem to work fine for me.
EDIT : Here is the crash dump for Ubuntu Noble, the crash also happens when using version 1.18.4 of the GUI and makemkvcon 2.0.0, but not the other way around, suggesting that the problem indeed stems from makemkvcon.
PID: 7904 (makemkvcon)
UID: 1000 (sayaka)
GID: 1001 (sayaka)
Signal: 11 (SEGV)
Timestamp: Sat 2026-09-26 20:02:19 CEST (6s ago)
Command Line: /usr/bin/makemkvcon guiserver A0001+shm
Executable: /usr/bin/makemkvcon
Control Group: /user.slice/user-1000.slice/
user@1000.service/app.slice/
app-makemkv@3dca7cfdd48a4a6aab29a92bf5e55c01.service
Unit:
user@1000.service
User Unit:
app-makemkv@3dca7cfdd48a4a6aab29a92bf5e55c01.service
Slice: user-1000.slice
Owner UID: 1000 (sayaka)
Boot ID: 5f05511e8b854d9887bdb8e1483f678d
Machine ID: da2da23db9b8b7696f6ac54d68514737
Hostname: [redacted]
Storage: /var/lib/systemd/coredump/core.makemkvcon.1000.5f05511e8b854d9887bdb8e1483f678d.7904.1790445739000000.zst (present)
Size on Disk: 13.3M
Message: Process 7904 (makemkvcon) of user 1000 dumped core.
Module libzstd.so.1 from deb libzstd-1.5.5+dfsg2-2build1.1.amd64
Module libgomp.so.1 from deb gcc-14-14.2.0-4ubuntu2~24.04.1.amd64
Module libgcc_s.so.1 from deb gcc-14-14.2.0-4ubuntu2~24.04.1.amd64
Module libstdc++.so.6 from deb gcc-14-14.2.0-4ubuntu2~24.04.1.amd64
Stack trace of thread 7905:
#0 0x000057752118a422 n/a (makemkvcon + 0x5a7422)
#1 0x000057752124188c n/a (makemkvcon + 0x65e88c)
#2 0x000057752122a39f n/a (makemkvcon + 0x64739f)
#3 0x0000577521227e5e n/a (makemkvcon + 0x644e5e)
#4 0x000057752117e796 n/a (makemkvcon + 0x59b796)
#5 0x000057752117dd10 n/a (makemkvcon + 0x59ad10)
#6 0x000057752117b9de n/a (makemkvcon + 0x5989de)
#7 0x000057752117faef n/a (makemkvcon + 0x59caef)
#8 0x00005775211e1dd9 n/a (makemkvcon + 0x5fedd9)
#9 0x00005775211e1782 n/a (makemkvcon + 0x5fe782)
#10 0x00005775211e0edc n/a (makemkvcon + 0x5fdedc)
#11 0x0000577521275bf8 n/a (makemkvcon + 0x692bf8)
#12 0x0000577521276827 n/a (makemkvcon + 0x693827)
#13 0x000072a905a9cb84 start_thread (libc.so.6 + 0x9cb84)
#14 0x000072a905b29ecc __clone3 (libc.so.6 + 0x129ecc)
Stack trace of thread 7904:
#0 0x000072a905a98e51 __futex_abstimed_wait_common64 (libc.so.6 + 0x98e51)
#1 0x000072a905a9e883 __pthread_clockjoin_ex (libc.so.6 + 0x9e883)
#2 0x0000577521314c9f n/a (makemkvcon + 0x731c9f)
#3 0x000057752113d68e n/a (makemkvcon + 0x55a68e)
#4 0x000072a905a2a1ca __libc_start_call_main (libc.so.6 + 0x2a1ca)
#5 0x000072a905a2a28b __libc_start_main_impl (libc.so.6 + 0x2a28b)
#6 0x0000577520f69c61 n/a (makemkvcon + 0x386c61)
Stack trace of thread 7907:
#0 0x000072a905b1bd6a __GI___libc_read (libc.so.6 + 0x11bd6a)
#1 0x0000577521315ac7 n/a (makemkvcon + 0x732ac7)
#2 0x000072a905a9cb84 start_thread (libc.so.6 + 0x9cb84)
#3 0x000072a905b29ecc __clone3 (libc.so.6 + 0x129ecc)
Stack trace of thread 7906:
#0 0x000072a905a98e51 __futex_abstimed_wait_common64 (libc.so.6 + 0x98e51)
#1 0x000072a905aa4e73 __new_sem_wait_slow64 (libc.so.6 + 0xa4e73)
#2 0x00005775213159bb n/a (makemkvcon + 0x7329bb)
#3 0x0000577521315183 n/a (makemkvcon + 0x732183)
#4 0x000072a905a9cb84 start_thread (libc.so.6 + 0x9cb84)
#5 0x000072a905b29ecc __clone3 (libc.so.6 + 0x129ecc)
Stack trace of thread 7943:
#0 0x000072a905a98e51 __futex_abstimed_wait_common64 (libc.so.6 + 0x98e51)
#1 0x000072a905aa5098 __new_sem_wait_slow64 (libc.so.6 + 0xa5098)
#2 0x00005775212767f8 n/a (makemkvcon + 0x6937f8)
#3 0x000072a905a9cb84 start_thread (libc.so.6 + 0x9cb84)
#4 0x000072a905b29ecc __clone3 (libc.so.6 + 0x129ecc)
Stack trace of thread 7932:
#0 0x000072a905a98e51 __futex_abstimed_wait_common64 (libc.so.6 + 0x98e51)
#1 0x000072a905aa5098 __new_sem_wait_slow64 (libc.so.6 + 0xa5098)
#2 0x00005775212767f8 n/a (makemkvcon + 0x6937f8)
#3 0x000072a905a9cb84 start_thread (libc.so.6 + 0x9cb84)
#4 0x000072a905b29ecc __clone3 (libc.so.6 + 0x129ecc)
Stack trace of thread 7931:
#0 0x000072a905a98e51 __futex_abstimed_wait_common64 (libc.so.6 + 0x98e51)
#1 0x000072a905aa5098 __new_sem_wait_slow64 (libc.so.6 + 0xa5098)
#2 0x00005775212767f8 n/a (makemkvcon + 0x6937f8)
#3 0x000072a905a9cb84 start_thread (libc.so.6 + 0x9cb84)
#4 0x000072a905b29ecc __clone3 (libc.so.6 + 0x129ecc)
ELF object binary architecture: AMD x86-64
