Firefox 94.0.1-1 won't start

Today I did a snap refresh and Firefox that was running at the time immediately disappeared and now it can’t be started again. Running it from the terminal outputs this:

/snap/firefox/701/firefox.launcher: 47: xdg-user-dir: not found
XPCOMGlueLoad error for file /snap/firefox/701/usr/lib/firefox/libmozgtk.so:
libgtk-3.so.0: cannot open shared object file: No such file or directory
Couldn't load XPCOM.

Note that Firefox didn’t actually update today as far as I can tell. I got v94 a couple of days ago.

Can you share the output of snap changes --abs-time?

883  Done    2021-11-09T03:41:41Z  2021-11-09T03:41:42Z  Change configuration of "core" snap
884  Done    2021-11-09T03:41:51Z  2021-11-09T03:42:30Z  Install "blender_3" snap from "3.0/beta" channel
885  Done    2021-11-09T07:17:19Z  2021-11-09T07:18:01Z  Refresh snap "blender_3"
886  Done    2021-11-09T10:15:35Z  2021-11-09T10:16:14Z  Refresh snap "skype"
887  Done    2021-11-09T11:01:26Z  2021-11-09T11:01:26Z  Refresh all snaps: no updates

It disappeared sometime around the 7:17 event I think. The configuration change was me enabling parallel installs so I could install blender 3 along side blender stable.

Can you share the output of snap list and snap connections firefox ?

al@al-desktop:~$ snap list
Name                     Version                      Rev    Tracking       Publisher           Notes
android-studio           2020.3.1.24                  115    latest/stable  snapcrafters        classic
arduino                  1.8.15                       61     latest/stable  merlijn-sebrechts   -
atom                     1.57.0                       282    latest/stable  snapcrafters        classic
bare                     1.0                          5      latest/stable  canonical✓          base
beaker-browser           0.8.10                       2      latest/stable  afterconnery        -
blender                  2.93.5                       830    latest/stable  blenderfoundation✓  classic
blender_3                3.0.0                        1051   3.0/beta       blenderfoundation✓  classic
chromium                 95.0.4638.69                 1810   latest/stable  canonical✓          -
clion                    2021.2.3                     169    latest/stable  jetbrains✓          classic
code                     b3318bc0                     79     latest/stable  vscode✓             classic
core                     16-2.52.1                    11993  latest/stable  canonical✓          core
core18                   20211015                     2246   latest/stable  canonical✓          base
core20                   20210928                     1169   latest/stable  canonical✓          base
cura-slicer              4.11.0                       52     latest/stable  glasen              -
datagrip                 2021.2.4                     121    latest/stable  jetbrains✓          classic
dc-tiledmap              1.4.2-16-g2ad9a874           5      latest/stable  diogocarneiro       -
emoj                     v2.0.0                       53     latest/stable  popey               -
fakecam                  2.2.0                        104    latest/stable  diddledani          -
firefox                  94.0.1-1                     701    latest/stable  mozilla✓            -
fsuae                    3.0.3                        73     latest/stable  jz                  -
gimp                     2.10.24                      372    latest/stable  snapcrafters        -
gnome-3-28-1804          3.28.0-19-g98f9e67.98f9e67   161    latest/stable  canonical✓          -
gnome-3-38-2004          0+git.6ba6040                76     latest/stable  canonical✓          -
gtk-common-themes        0.1-59-g7bca6ae              1519   latest/stable  canonical✓          -
gtk2-common-themes       0.1                          13     latest/stable  canonical✓          -
gzdoom                   4.6                          57     latest/stable  rs-bjerg            -
inkscape                 1.1.1-eb90963e84-2021-10-02  9256   latest/stable  inkscape✓           -
intellij-idea-community  2021.2.3                     330    latest/stable  jetbrains✓          classic
kde-frameworks-5-core18  5.61.0                       32     latest/stable  kde✓                -
mame                     mame0231                     2424   latest/stable  popey               -
mate-wayland             0+git.e9e98c0                449    latest/edge    wmww                classic
meshlab                  2021.05                      183    latest/stable  cnr-isti-vclab      -
mosquitto                2.0.13                       675    latest/stable  mosquitto✓          -
mqtt-explorer            0.3.5                        29     latest/stable  thomasnordquist     -
multipass                1.8.0                        6130   latest/stable  canonical✓          -
netbeans                 12.5                         50     latest/stable  apache-netbeans✓    classic
obs-studio               27.1.0-rc1                   x17    latest/stable  -                   try
openscad                 2021.01                      190    latest/stable  torsten-paul        -
openscad-nightly         0+git.5736bf586              2926   latest/stable  torsten-paul        -
protracker               1.25-4d6376b                 157    latest/stable  cmatsuoka           -
pycharm-community        2021.2.3                     256    latest/stable  jetbrains✓          classic
pycharm-professional     2021.2.3                     260    latest/stable  jetbrains✓          classic
sigrok-suite             2019-07-29-2-master          51     latest/edge    smslv               -
skype                    8.78.0.161                   190    latest/stable  skype✓              -
slack                    4.21.1                       47     latest/stable  slack✓              classic
snapcraft                5.0                          6751   latest/stable  canonical✓          classic
sublime-text             4121                         110    latest/stable  snapcrafters        classic
tiled                    1.7.2                        3046   latest/stable  bjorn               -
upnp-server              0.1.0                        1      latest/stable  ogra                -
webstorm                 2021.2.3                     227    latest/stable  jetbrains✓          classic
al@al-desktop:~$ snap connections firefox
Interface                 Plug                            Slot                             Notes
audio-playback            firefox:audio-playback          :audio-playback                  -
audio-record              firefox:audio-record            :audio-record                    -
avahi-observe             firefox:avahi-observe           :avahi-observe                   -
browser-support           firefox:browser-sandbox         :browser-support                 -
camera                    firefox:camera                  :camera                          -
content[gnome-3-38-2004]  firefox:gnome-3-38-2004         gnome-3-38-2004:gnome-3-38-2004  -
content[gtk-3-themes]     firefox:gtk-3-themes            gtk-common-themes:gtk-3-themes   -
content[icon-themes]      firefox:icon-themes             gtk-common-themes:icon-themes    -
content[sound-themes]     firefox:sound-themes            gtk-common-themes:sound-themes   -
cups-control              firefox:cups-control            :cups-control                    -
dbus                      -                               firefox:dbus-daemon              -
desktop                   firefox:desktop                 :desktop                         -
desktop-legacy            firefox:desktop-legacy          :desktop-legacy                  -
gsettings                 firefox:gsettings               :gsettings                       -
hardware-observe          firefox:hardware-observe        :hardware-observe                -
home                      firefox:home                    :home                            -
joystick                  firefox:joystick                -                                -
mpris                     -                               firefox:mpris                    -
network                   firefox:network                 :network                         -
network-observe           firefox:network-observe         -                                -
opengl                    firefox:opengl                  :opengl                          -
personal-files            firefox:dot-mozilla-firefox     :personal-files                  -
removable-media           firefox:removable-media         :removable-media                 -
screen-inhibit-control    firefox:screen-inhibit-control  :screen-inhibit-control          -
system-files              firefox:etc-firefox-policies    :system-files                    -
system-packages-doc       firefox:system-packages-doc     :system-packages-doc             -
u2f-devices               firefox:u2f-devices             :u2f-devices                     -
unity7                    firefox:unity7                  :unity7                          -
upower-observe            firefox:upower-observe          :upower-observe                  -
wayland                   firefox:wayland                 :wayland                         -
x11                       firefox:x11                     :x11                             -

Everything looks in order here, I wonder what’s going on.

What’s the output of snap run firefox -version ?

Identical to my first message.

Rebooting fixed it. ???

Huh, that’s weird. I don’t know what happened, but I’m glad that at least the problem is gone for you.