Desktop Team Updates - Monday 1st November 2021

Hi everyone, below you will find the updates from the Desktop team from the last week. If you’re interested in discussing a topic please start a thread in the Desktop area of Discourse .

Last week’s notes are here: Desktop Team Updates - Monday 25th October 2021

1 Like
  • Working on adding reboot/shutdown feature on Ubuntu for WSL launcher side
  • Working on the automatic detection of GUI/TUI mode on Ubuntu for WSL launcher side
  • 22.04 Roadmap sprint.
  • Answered lots of bugs in Launchpad and upstreams (backlog stats are here).
  • Triple buffering progress:
    • Spent most of the week fixing and rewriting handling of monitor power saving modes, something I had neglected till now. This means app rendering is throttled while the screen is off, no warnings/assertions are reported, and the monitor turns back on reliably.
    • More Nvidia testing.
  • Explored using ClutterOffscreenEffect to implement localised triple buffering. It would allow any part of the screen to animate with the smoothness of triple buffering, without needing backend support. Not working yet but actually I think full screen triple buffering is more useful and closer to finished.
  • Reviewing and grading job applications again.

Desktop Installer

Firmware Updater


  • Participated to the Canonical roadmap sessions
  • Started working on defining the different workitems for the cycle
  • Distro
    • updated the evince apparmor profile to use the xubuntu abstraction
    • opensc, opened a bug and patch to Debian to add a .symbols as requested in the MIR review
    • fixed the cheese build failing due to Bsymbolic-function
    • investigated firefox snap not working with orca, turns out recent at-spi had changed that made it stop working for snaps. Thanks James for the details and opening a forum discussion
    • Did some of the pending desktop merges
  • Snaps
    • updated some GNOME snap to the new stable serie, workarounded a build issue by forcing some to an old version for meson
    • switched the thunderbird snaps to use core20
    • updated the thunderbird beta snap to 94.0b5
    • fixed the eog snap not starting following an accidental libportal soname change in the gnome sdk
  • New Desktop Installer
    • started playing with weblate up evaluate it for ubuntu-desktop-installer translations
  • Sponsoring and reviews
    • sponsored the new libfprint version from Trevinho
    • discussed a bit the proposed fix for canary offline installations
    • sponsored alsa-lib fixes from oem
    • uploaded the gnome-keyring merge from ricotz
    • uploaded the libfprint amrhf build fix from Trevinho
  • Reports
    • included firefox in the snaps report
    • worked on a script to check which revisions of our snaps need to be rebuild for CVE fixes in staged packages
    • included the CVE informations in the snaps report
  • Other
    • reviewed applications for the desktop position
  • LO snap build fixed and tested it and left it in candidate for a few days. Released to stable today.
  • sorted out so that is all updated for impish/jammy
  • Indaba!!!

firefox24 firefox

chromium22 chromium

  • updated stable to 95.0.4638.69
  • updating beta to 96.0.4664.27
  • updating dev to 97.0.4682.3
  • updated the enable-pipewire branch and rebased it on 96.0.4664.18, then merged into the beta and dev branches
  • added WebRTC to the manual test plan

snapcraft24 snaps

flutter24 Ubuntu Desktop Installer

  • CUPS Snap: Waiting for @ijohnson’s pull request on snapd for the cups printing interface to get merged by the snapd team (ETA: October). @ijohnson has now implemented what @pedronis and @jamesh have requested in the PR, so it gets closer to merging. @mardy approves PR.
  • cups-filters: Ported CUPS’ PPD compiler (ppdc) into libppd (commit 1, commit 2, commit 3). This way also classic CUPS using /usr/share/cups/drv/*.drv files instead of physical PPDs can get straightforwardly encapsulated into Printer Applications with pappl-retrofit now. So all PPD handling functionality of CUPS is ported to cups-filters now and all types of classic CUPS printer drivers can get easily converted to Printer Applications. Improved bannertopdf() filter function to integrate in pappl-retrofit more easily, to allo PDF-based test pages, easier to customize for the specific Printer Application, no need of PostScript interpreter (commit).
  • pappl-retrofit: We have 4 Printer Application Snaps now ( Support for on-the-fly PPDs via *.drv files ( Now the Test Printer Application includes all classic CUPS drivers installed on the system. Support for PDF-based dynamic test pages via the bannertopdf() filter function (commit). Save copy of what goes to the printer when running in debug logging mode (commit). Improved matching of printer’s device ID with PPD files and representation of PPD files in driver list.
  • Retro-fitting Printer Applications: Make use of libppd’s *.drv support in the Snaps (commit), more precise determination of files in the Snap (commit), patched dnssd CUPS backend to only report JetDirect/Port 9100 not IPP or LPD (commit), switched to the PDF-based dynamic test page (commit), Corrected passing of arguments in startup script for the Snap (commit), also added missing pdftops CUPS filter (needed by foomatic-rip) to the Ghostscript Printer Application Snap.
  • OpenPrinting: Started working on a way to allow querying the web site with a printer device ID and get back a list of the Printer Applications supporting this printer and the preferred Printer Application under them. The idea is to install all Printer Applications from the Snap Store on the web server, stop their daemons (we only want to query, not print), keep auto-updating from the Snap Store, and have a CGI script which can be called with a URL containing the device ID, query the device ID on all Printer Applications, and return the list of suitable Printer Applications in desirability order as plain text, so that a printer setup tool can easily use it.
  • Bugs.


  • Help on scoping for next cycle
  • Finish MIR review and wsl-setup reupload. Now acked!
  • Play with theming on Windows Terminal
  • Fixed upgrade manager compatibility with WSL (no snap support)
  • Debug time syncing issues (rabbit hole)

1 day off


  • Reviews on gjs promise GSource
  • Some fixes on the dock, preparing yaru side of fixes too
  • Various libfprint, fprintd and dbus-mock fixes
  • More libfprint-TOD fixes and relased v1.94.1-TOD1




  • Finished the ‘prefill’ feature. Subiquity TUI and Flutter GUI now can start with language and user name pre set from Windows environment.
  • Working now on locale setup, since we cannot rely on Cloud-Init under WSL.