[snap] Chromium with core24 base won't start: desktop-launch not found

[Tom]

Today I was prompted to update my chromium snap, so I closed it down and the auto-refresh happened. When I tried to launch it, it did not come up. Running `chromium` from the command line resulted in the following error:

$ chromium
Content snap command-chain for /snap/chromium/2905/gnome-platform/command-chain/desktop-launch not found: ensure slot is connected

Browsing the internet, I found people saying that gnome needed to be connected. Running `sudo snap connect chromium:gnome-46-2404 gnome-46-2404:gnome-46-2404` did not fix the problem.

I'm not sure it matters for a snap, but this is (very recently updated) ubuntu 22.04 running KDE on x86_64.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Maxim Wirt (mvirt)]

The same error on Ubuntu 24.04 / x86_64

[Dr Maria Brandl (regenspatz)]

Same on Ubuntu 18.04.

sudo snap revert chromium --revision 2897

took me back to the previous, functioning version of chromium.

snap refresh --hold=24h chromium

is also useful to stop further updates for a while.

[Serik Kozhabaev (shiko15)]

As it was suggested by the people above, I ran this command below
> sudo snap revert chromium --revision 2897
But for some reason it gives me this error message:
error: cannot revert "chromium": cannot revert inactive snaps

[Mingi Hwang (goonmandu)]

Can confirm on Ubuntu 20.04, amd64, but with different error message.

$ chromium

Content snap command-chain for /snap/chromium/2905/gpu-2404/bin/gpu-2404-provider-wrapper not found: ensure slot is connected

$ snap info chromium

name: chromium
summary: Chromium web browser, open-source version of Chrome
publisher: Canonical✓
store-url: https://snapcraft.io/chromium
contact: https://bugs.launchpad.net/ubuntu/+source/chromium-browser/+bugs?field.tag=snap
license: unset
description: |
  An open-source browser project that aims to build a safer, faster, and more
  stable way for all Internet users to experience the web.
commands:
  - chromium.chromedriver
  - chromium
snap-id: XKEcBqPM06H1Z7zGOdG5fbICuf8NWK5R
tracking: latest/stable
refresh-date: today at 09:30 KST
channels:
  latest/stable: 126.0.6478.126 2024-07-04 (2905) 174MB -
  latest/candidate: 126.0.6478.126 2024-07-03 (2905) 174MB -
  latest/beta: 127.0.6533.26 2024-06-28 (2904) 179MB -
  latest/edge: 128.0.6555.2 2024-06-26 (2898) 180MB -
installed: 126.0.6478.126 (2905) 174MB

Reverting to Revision 2897 as mentioned in #3 solved the issue.

[Nathan Teodosio (nteodosio)]

Can you also please add the result

  snap info --verbose chromium|grep -q core24 && { snap connections chromium; snap list|grep -P 'mesa|gnome-\d|core2'; }

if not empty? (Stable was rolled back to use core22 to fix the problem so if you already got it updated it will return nothing).

[Dr Maria Brandl (regenspatz)]

Not sure how to address #4, but wonder whether revision 2897 is available on his installation.
On my computer:
ls -l /snap/chromium/
produced:
drwxr-xr-x 12 root root 190 Jun 25 18:31 2897
drwxr-xr-x 11 root root 179 Jul 3 17:23 2905
lrwxrwxrwx 1 root root 4 Jul 7 16:45 current -> 2897

[Nathan Teodosio (nteodosio)]

I reverted Chromium stable channel to core22 (revisions 2897 for x64 and 2899 for aarch64). It would still be valuable to investigate what exactly is going on here with core24 (on candidate channel, revisions 2905 and 2906), which is what triggered this bug, especially regarding the connections as asked in #6 and #7.

[Dr Maria Brandl (regenspatz)]

snap list | grep -E 'gpu|gnome|core2'

produces:

core20 20240416 2318 latest/stable canonical** base
core22 20240408 1380 latest/stable canonical** base
core24 20240528 423 latest/stable canonical** base
gnome-3-26-1604 3.26.0.20221130 111 latest/stable/… canonical** -
gnome-3-28-1804 3.28.0-19-g98f9e67.98f9e67 198 latest/stable canonical** -
gnome-3-34-1804 0+git.3556cb3 93 latest/stable canonical** -
gnome-3-38-2004 0+git.efb213a 143 latest/stable canonical** -
gnome-42-2204 0+git.510a601 176 latest/stable canonical** -
gnome-46-2404 0+git.b6706a3 26 latest/stable canonical** -
gnome-calculator 45.0.2 955 latest/stable/… canonical** -
gnome-characters 46.0 797 latest/stable/… canonical** -
gnome-logs 45.0 123 latest/stable/… canonical** -
gnome-system-monitor 45.0 186 latest/stable/… canonical** -
kde-frameworks-5-96-qt-5-15-5-core20 5.96.0 7 latest/stable kde** -
kf5-5-104-qt-5-15-8-core22 5.104 9 latest/stable kde** -
kf5-5-108-qt-5-15-10-core22 5.108 5 latest/stable kde** -
kf5-5-111-qt-5-15-11-core22 5.111 7 latest/stable kde** -
kf5-5-113-qt-5-15-11-core22 5.113 1 latest/stable kde** -
mesa-core22 23.2.1 311 latest/stable canonical** -

[Dr Maria Brandl (regenspatz)]

snap connections chromium

returns:

Interface Plug Slot Notes
audio-playback chromium:audio-playback :audio-playback -
audio-record chromium:audio-record :audio-record -
bluez chromium:bluez :bluez -
browser-support chromium:browser-sandbox :browser-support -
camera chromium:camera :camera -
content chromium:foo-install-cups - -
content[gnome-46-2404] chromium:gnome-46-2404 gnome-46-2404:gnome-46-2404 -
content[gpu-2404] chromium:gpu-2404 mesa-2404:gpu-2404 -
content[gtk-3-themes] chromium:gtk-3-themes gtk-common-themes:gtk-3-themes -
content[icon-themes] chromium:icon-themes gtk-common-themes:icon-themes -
content[sound-themes] chromium:sound-themes gtk-common-themes:sound-themes -
cups chromium:cups cups:cups -
desktop chromium:desktop :desktop -
desktop-legacy chromium:desktop-legacy :desktop-legacy -
gsettings chromium:gsettings :gsettings -
hardware-observe chromium:hardware-observe :hardware-observe -
home chromium:home :home -
joystick chromium:joystick :joystick -
mount-observe chromium:mount-observe - -
mpris - chromium:mpris -
network chromium:network :network -
network-bind chromium:network-bind :network-bind -
network-manager chromium:network-manager - -
opengl chromium:opengl :opengl -
password-manager-service chromium:password-manager-service - -
personal-files chromium:chromium-config :personal-files -
personal-files chromium:dot-local-share-applications :personal-files -
personal-files chromium:dot-local-share-icons :personal-files -
raw-usb chromium:raw-usb - -
removable-media chromium:removable-media :removable-media -
screen-inhibit-control chromium:screen-inhibit-control ...

[Nathan Teodosio (nteodosio)]

Hi Dr Maria Brandl, thanks but it seems you already got the snap reverted to the core22 version so this won't be of use for debugging. I updated #6 to make that clearer.

[Dr Maria Brandl (regenspatz)]

Reverted back to revision 2905 and updated #10 and #11.

Revision 2905 now behaves as expected, also resilient to operating system shutdown and restart.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Dr Maria Brandl (regenspatz)]

Being back on revision 2905:

snap info --verbose chromium|grep -q core24 && { snap connections chromium; snap list|grep -P 'mesa|gnome-\d|core2'; }

returns:

snap info --verbose chromium|grep -q core24 && { snap connections chromium; snap list|grep -P 'mesa|gnome-\d|core2'; }
Interface Plug Slot Notes
audio-playback chromium:audio-playback :audio-playback -
audio-record chromium:audio-record :audio-record -
bluez chromium:bluez :bluez -
browser-support chromium:browser-sandbox :browser-support -
camera chromium:camera :camera -
content chromium:foo-install-cups - -
content[gnome-46-2404] chromium:gnome-46-2404 gnome-46-2404:gnome-46-2404 -
content[gpu-2404] chromium:gpu-2404 mesa-2404:gpu-2404 -
content[gtk-3-themes] chromium:gtk-3-themes gtk-common-themes:gtk-3-themes -
content[icon-themes] chromium:icon-themes gtk-common-themes:icon-themes -
content[sound-themes] chromium:sound-themes gtk-common-themes:sound-themes -
cups chromium:cups cups:cups -
desktop chromium:desktop :desktop -
desktop-legacy chromium:desktop-legacy :desktop-legacy -
gsettings chromium:gsettings :gsettings -
hardware-observe chromium:hardware-observe :hardware-observe -
home chromium:home :home -
joystick chromium:joystick :joystick -
mount-observe chromium:mount-observe - -
mpris - chromium:mpris -
network chromium:network :network -
network-bind chromium:network-bind :network-bind -
network-manager chromium:network-manager - -
opengl chromium:opengl :opengl -
password-manager-service chromium:password-manager-service - -
personal-files chromium:chromium-config :personal-files -
personal-files chromium:dot-local-share-applications :personal-files -
personal-files chromium:dot-local-share-icons :personal-files -
raw-usb ...

[Tom (teeks99)]

I can confirm that after a `snap refresh` I'm at 2897 and things are back to working order.

[Jim Muchow (jdavidm)]

My version of this bug was declared a duplicate (which it is). As I wrote, I simply reset my box and the problem was "fixed" and it has stayed so. I don't know what that means.

xyz@optiplex:~$ ls -al /snap/chromium
total 8
drwxr-xr-x 4 root root 4096 Jul 5 06:37 .
drwxr-xr-x 22 root root 4096 Jul 5 06:36 ..
drwxr-xr-x 12 root root 190 Jun 25 12:31 2897
drwxr-xr-x 11 root root 179 Jul 3 11:23 2905
lrwxrwxrwx 1 root root 4 Jul 5 06:32 current -> 2905

Is there anything more I can do to help?

[Serik Kozhabaev (shiko15)]

I tried other old solutions on the Internet before I found this thread so unfortunately in #4 I deleted my chromium along with its configs and data. I reinstalled 2897 and now everything works fine but my extensions/bookmarks/history are all lost(

[Nathan Teodosio (nteodosio)]

#4 does not cause Chromium configuration and data files to be deleted.

Look into $HOME/snap/chromium or even for saved snapshots with 'snap saved'.

[Nathan Teodosio (nteodosio)]

Jim Muchow, no, thank you, the problem is under investigation by the Snapd team.

[Alessandro Astone (aleasto)]

This might not end up being related, but interesting nonetheless:
I was hacking on the stable Firefox snap using https://snapcraft.io/overlay

After mounting the overlay `sudo /snap/overlay/current/overlay $(realpath /snap/firefox/current)` I tried to start firefox and it did not launch. I haven't seen this happening with other snaps. The journal contains:

Aug 01 10:40:59 thinkpad kernel: audit: type=1400 audit(1722501659.347:4687): apparmor="DENIED" operation="open" class="file" profile="snap-update-ns.firefox" name="/proc/379042/maps" pid=379042 comm="5" requested_mask="r" denied_mask="r" fsuid=1000 ouid=0
Aug 01 10:40:59 thinkpad firefox_firefox.desktop[379021]: Content snap command-chain for /snap/firefox/4630/gnome-platform/command-chain/desktop-launch not found: ensure slot is connected

Do we know if this bug also came with the AppArmor denial?

[Nathan Teodosio (nteodosio)]

No.

[Alessandro Astone (aleasto)]

No we don't know, or no it did not have an AppArmor denial? :P

[Nathan Teodosio (nteodosio)]

No, we don't know. xD

I think all we know is what users reported here. As unfortunately no one
could figure out a reproduction recipe for the issue.

[Nathan Teodosio (nteodosio)]

You are very likely on to something with your investigation, I think: The
Apparmor error is quite weird, as

  % grep /maps /var/lib/snapd/apparmor/profiles/snap-update-ns.chromium
  owner @{PROC}/@{pid}/maps r,

The core24 snap still exists in --channel stable/core24-lp2072395 and install
as I may it, I don't hit the bug.

[Alessandro Astone (aleasto)]

Actually I see `apparmor="DENIED" operation="open" class="file" profile="snap-update-ns.firefox" name="/proc/379042/maps" pid=379042 comm="5" requested_mask="r" denied_mask="r" fsuid=1000 ouid=0` in my journal for all snaps, so might not be the cause afterall.

[Nathan Teodosio (nteodosio)]

My understanding is that this is in progress on Snapd's side as per Zyga's report.

[Intermittent-bug-filer (intermittent-bug-filer)]

**Filed by:** amarc [at] mozilla.com
**Parsed log:** https://treeherder.mozilla.org/logviewer?job_id=500488754&repo=mozilla-central
**Full log:** https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/Wo9dYVitRo-gMSPnbLLZLQ/runs/0/artifacts/public/logs/live_backing.log

---
```
[task 2025-03-23T02:31:26.167Z] Building wheels for collected packages: mozlog
[task 2025-03-23T02:31:26.168Z] Building wheel for mozlog (setup.py): started
[task 2025-03-23T02:31:26.399Z] Building wheel for mozlog (setup.py): finished with status 'done'
[task 2025-03-23T02:31:26.400Z] Created wheel for mozlog: filename=mozlog-8.0.0-py2.py3-none-any.whl size=69608 sha256=73f30afb9ae230a5abcf0bc00d91f5cf600a03057d8cf66bd40d8abda35430fd
[task 2025-03-23T02:31:26.400Z] Stored in directory: /home/task_174269682053351/.cache/pip/wheels/f3/04/57/02f3d25fa74ca7a408a80e1b4892033a55c233229f7cc0b858
[task 2025-03-23T02:31:26.401Z] Successfully built mozlog
[task 2025-03-23T02:31:26.744Z] Installing collected packages: wcwidth, sortedcontainers, urllib3, sniffio, PyYAML, PySocks, Pillow, mozterm, mozfile, idna, h11, exceptiongroup, certifi, blessed, attrs, wsproto, outcome, mozlog, trio, trio-websocket, selenium
[task 2025-03-23T02:31:27.372Z] WARNING: The script structlog is installed in '/home/task_174269682053351/.local/bin' which is not on PATH.
[task 2025-03-23T02:31:27.372Z] Consider adding this directory to PATH or, if you prefer to suppress this warning, use --no-warn-script-location.
[task 2025-03-23T02:31:28.218Z] Successfully installed Pillow-10.1.0 PySocks-1.7.1 PyYAML-6.0.1 attrs-23.1.0 blessed-1.20.0 certifi-2023.7.22 exceptiongroup-1.1.3 h11-0.14.0 idna-3.4 mozfile-3.0.0 mozlog-8.0.0 mozterm-1.0.0 outcome-1.2.0 selenium-4.12.0 sniffio-1.3.0 sortedcontainers-2.4.0 trio-0.22.2 trio-websocket-0.10.4 urllib3-2.0.5 wcwidth-0.2.13 wsproto-1.2.0
[task 2025-03-23T02:31:28.328Z] + export TEST_NO_HEADLESS=1
[task 2025-03-23T02:31:28.328Z] + TEST_NO_HEADLESS=1
[task 2025-03-23T02:31:28.328Z] + '[' -n '' ']'
[task 2025-03-23T02:31:28.328Z] + RECORD_SCREEN_PID=0
[task 2025-03-23T02:31:28.328Z] + '[' '' = true ']'
[task 2025-03-23T02:31:28.328Z] + '[' basic = basic ']'
[task 2025-03-23T02:31:28.328Z] + sed -e s/#RUNTIME_VERSION#/command-chain/#
[task 2025-03-23T02:31:28.330Z] + python3 basic_tests.py basic_tests/expectations.json
[task 2025-03-23T02:31:58.595Z] Traceback (most recent call last):
[task 2025-03-23T02:31:58.595Z] File "/task_174269682053351/fetches/basic_tests.py", line 556, in <module>
[task 2025-03-23T02:31:58.595Z] SnapTests(exp=sys.argv[1])
[task 2025-03-23T02:31:58.595Z] File "/task_174269682053351/fetches/basic_tests.py", line 384, in __init__
[task 2025-03-23T02:31:58.595Z] super(SnapTests, self).__init__(exp)
[task 2025-03-23T02:31:58.595Z] File "/task_174269682053351/fetches/basic_tests.py", line 87, in __init__
[task 2025-03-23T02:31:58.595Z] self._driver = webdriver.Firefox(service=driver_service, options=options)
[task 2025-03-23T02:31:58.595Z] File "/home/task_174269682053351/.local/lib/python3.10/site-packages/selenium/webdriver/firefox/webdriver.py", line 60, in __init__
[task 2025-03-23T02:31:58.596Z] self.s...

[Lissyx+mozillians (lissyx+mozillians)]

From https://firefoxci.taskcluster-artifacts.net/Wo9dYVitRo-gMSPnbLLZLQ/0/public/build/geckodriver.log

`Content snap command-chain for /snap/firefox/x1/gnome-platform/command-chain/desktop-launch not found: ensure slot is connected`

Nathan, is this the famous core22 to core24 migration issue?

[Lissyx+mozillians (lissyx+mozillians)]

And if so, what is the way to fix it? Locally I could never get anything to work when it happened until I did a reboot, but on CI it's not going to be effective.

[Orangefactor (orangefactor)]

## Summary
1 failures in 5035 pushes (0.0 failures/push) were associated with this bug in the last 7 days.

## Repository breakdown:
* mozilla-central: 1

## Platform and build breakdown:
* linux64-snap-amd64-2204-stablecore24: 1
  * opt: 1

## Table
| |**no_variant**|
|---|:-:|
|**linux64-snap-amd64-2204-stablecore24--/opt**|1|

## For more details, see:
https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=1955800&startday=2025-03-17&endday=2025-03-23&tree=all

[Nathan Teodosio (nteodosio)]

> Nathan, is this the famous core22 to core24 migration issue?

Yes, it's https://launchpad.net/bugs/2072395.

> And if so, what is the way to fix it?

None is known to date, which is why we are holding every snap away from core24 while Snapd folks fight the bug.

[hideou aoi (aoilinux)]

Can anyone tell me which bug in snapd affect this?

[Orangefactor (orangefactor)]

2 failures were associated with this bug in the last 7 days.

## Repository breakdown:
* mozilla-central: 2

## Table
| |**no_variant**|
|---|:-:|
|**linux-x86/debug**|2|

## For more details, see:
https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=1955800&startday=2025-12-15&endday=2025-12-21&tree=all

[Maciej Borzecki (maciek-borzecki)]

Hi,

We landed a change which is likely to address this problem. It's currently available only in snapd edge, but will be included in the upcoming 2.74 release (likely to hit beta next week).

It'd be great if folks who observed the issue previously could try to update snapd and attempt to reproduce the same conditions as before.

Maciej