T430 upgraded from 18.04 to 20.04 Ubuntu MATE on Sunday.
Mumble snap worked prior to upgrade.
Removed and then re-installed Mumble, same issue occurs:
$ mumble
Qt: Session management error: None of the authentication protocols specified are supported
connect(2) call to /dev/shm/jack-1000/default/jack_0 failed (err=No such file or directory)
exec of JACK server (command = “/usr/bin/jackd”) failed: No such file or directory
connect(2) call to /dev/shm/jack-1000/default/jack_0 failed (err=No such file or directory)
connect(2) call to /dev/shm/jack-1000/default/jack_0 failed (err=No such file or directory)
connect(2) call to /dev/shm/jack-1000/default/jack_0 failed (err=No such file or directory)
connect(2) call to /dev/shm/jack-1000/default/jack_0 failed (err=No such file or directory)
connect(2) call to /dev/shm/jack-1000/default/jack_0 failed (err=No such file or directory)
attempt to connect to server failed
2020-03-03 14:19:22.425 JackAudioSystem: unable to open client due to 2 errors:
2020-03-03 14:19:22.425 JackAudioSystem: JackFailure - overall operation failed
2020-03-03 14:19:22.425 JackAudioSystem: JackServerFailed - unable to connect to the JACK server
2020-03-03 14:19:23.431 G15LCDEngineUnix: Unable to connect to G15Daemon.
2020-03-03 14:19:23.431 libopus 1.2.1 from /snap/mumble/665/bin/libopus.so.0
2020-03-03 14:19:23.433 CELT bitstream 8000000b from /snap/mumble/665/bin/libcelt0.so.0.7.0
2020-03-03 14:19:23.434 CELT bitstream 80000010 from /snap/mumble/665/bin/libcelt0.so.0.11.0
2020-03-03 14:19:23.435 Theme: “Mumble”
2020-03-03 14:19:23.435 Style: “Lite”
2020-03-03 14:19:23.435 --> qss: “:themes/Mumble/Lite.qss”
2020-03-03 14:19:23.436 Locale is “en_US” (System: “en_US”)
2020-03-03 14:19:23.449 propsReply “An AppArmor policy prevents this sender from sending this message to this recipient; type=“method_call”, sender=”:1.1292" (uid=1000 pid=74893 comm="/snap/mumble/665/bin/mumble " label=“snap.mumble.mumble (enforce)”) interface=“org.freedesktop.DBus.Properties” member=“GetAll” error name="(unset)" requested_reply=“0” destination=“org.freedesktop.NetworkManager” (uid=0 pid=1303 comm="/usr/sbin/NetworkManager --no-daemon " label=“unconfined”)"
2020-03-03 14:19:23.449 nmReply “An AppArmor policy prevents this sender from sending this message to this recipient; type=“method_call”, sender=”:1.1292" (uid=1000 pid=74893 comm="/snap/mumble/665/bin/mumble " label=“snap.mumble.mumble (enforce)”) interface=“org.freedesktop.NetworkManager” member=“GetDevices” error name="(unset)" requested_reply=“0” destination=“org.freedesktop.NetworkManager” (uid=0 pid=1303 comm="/usr/sbin/NetworkManager --no-daemon " label=“unconfined”)"
2020-03-03 14:19:23.450 “Object path cannot be empty”
2020-03-03 14:19:23.460 Database SQLite: “3.22.0”
2020-03-03 14:19:23.463 Overlay: Removing old socket on “/run/user/1000/snap.mumble/MumbleOverlayPipe”
2020-03-03 14:19:23.464 Overlay: Listening on “/run/user/1000/snap.mumble/MumbleOverlayPipe”
2020-03-03 14:19:23.469 Updating application palette
2020-03-03 14:19:23.486 GlobalShortcutX: Using XI2 2.3
Fontconfig warning: FcPattern object weight does not accept value [50 200)
The application (or it’s libraries) caught a Segmentation Fault. Backtrace follows:
Backtrace: /snap/mumble/665/usr/lib/x86_64-linux-gnu/libg15daemon_client.so.1(+0xdb3) [0x7fb924be6db3]
Backtrace: /lib/x86_64-linux-gnu/libpthread.so.0(+0x12890) [0x7fb9207dc890]
Backtrace: /snap/mumble/665/usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5(+0xa0a11) [0x7fb9180d7a11]
Backtrace: /snap/mumble/665/usr/lib/x86_64-linux-gnu/libQt5Gui.so.5(+0x1d4b21) [0x7fb921da3b21]
Backtrace: /snap/mumble/665/usr/lib/x86_64-linux-gnu/libQt5Gui.so.5(_ZN13QFontDatabase8findFontERK8QFontDefi+0x11d) [0x7fb921da719d]
Backtrace: /snap/mumble/665/usr/lib/x86_64-linux-gnu/libQt5Gui.so.5(_ZN13QFontDatabase4loadEPK12QFontPrivatei+0x346) [0x7fb921da79c6]
Backtrace: /snap/mumble/665/usr/lib/x86_64-linux-gnu/libQt5Gui.so.5(_ZNK12QFontPrivate15engineForScriptEi+0xc3) [0x7fb921d7d423]
Backtrace: /snap/mumble/665/usr/lib/x86_64-linux-gnu/libQt5Gui.so.5(_ZNK12QFontMetrics6heightEv+0x13) [0x7fb921d9d523]
Backtrace: /snap/mumble/665/usr/lib/x86_64-linux-gnu/libQt5Gui.so.5(+0x289c18) [0x7fb921e58c18]
Backtrace: /snap/mumble/665/usr/lib/x86_64-linux-gnu/libQt5Gui.so.5(_ZN4QCss14ValueExtractor11lengthValueERKNS_11DeclarationE+0xfa) [0x7fb921e62cda]
Backtrace: /snap/mumble/665/usr/lib/x86_64-linux-gnu/libQt5Gui.so.5(ZN4QCss14ValueExtractor15extractGeometryEPiS1_S1_S1_S1_S1+0x125) [0x7fb921e62ec5]
Backtrace: /snap/mumble/665/usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5(+0x1f0c8e) [0x7fb922528c8e]
Backtrace: /snap/mumble/665/usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5(+0x1f2cf6) [0x7fb92252acf6]
Backtrace: /snap/mumble/665/usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5(+0x1f3050) [0x7fb92252b050]
Backtrace: /snap/mumble/665/usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5(+0x1f5d86) [0x7fb92252dd86]
Backtrace: /snap/mumble/665/usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5(+0x2ead51) [0x7fb922622d51]
Backtrace: /snap/mumble/665/usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5(+0x23b173) [0x7fb922573173]
Backtrace: /snap/mumble/665/usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5(_ZN26QAbstractScrollAreaPrivate4initEv+0xcf) [0x7fb9225741ef]
Backtrace: /snap/mumble/665/usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5(_ZN17QAbstractItemViewC1ER24QAbstractItemViewPrivateP7QWidget+0x9) [0x7fb9226d7469]
Backtrace: /snap/mumble/665/usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5(_ZN9QTreeViewC2EP7QWidget+0x1a5) [0x7fb92273c0c5]
Backtrace: /snap/mumble/665/bin/mumble(+0x1c1946) [0x563105a16946]
Backtrace: /snap/mumble/665/bin/mumble(+0xe6922) [0x56310593b922]
Backtrace: /snap/mumble/665/bin/mumble(+0xe06e4) [0x5631059356e4]
Backtrace: /snap/mumble/665/bin/mumble(+0x6ce8c) [0x5631058c1e8c]
Backtrace: /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xe7) [0x7fb91fabbb97]
Backtrace: /snap/mumble/665/bin/mumble(+0x7056a) [0x5631058c556a]
End of Backtrace.
2020-03-03 14:19:23.833 QMutex: destroying locked mutex