snapd not setting XDG_DATA_DIRS correctly

[Hadmut Danisch]

Hi,

I'm just trying to figure out why Lubuntu does not offer snap-installed apps like Chromium-Browser in the desktop application launcher.

snapd is supposed to patch /var/lib/snapd/desktop into environment variable XDG_DATA_DIRS, which it doesn't do (at least under Lubuntu):

% echo $XDG_DATA_DIRS
/usr/share/Lubuntu:/usr/local/share/:/usr/share/:/usr/share

That's why snap-apps are not found.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: snapd 2.45.1+20.04
ProcVersionSignature: Ubuntu 5.4.0-37.41-generic 5.4.41
Uname: Linux 5.4.0-37-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.3
Architecture: amd64
CasperMD5CheckResult: skip
CurrentDesktop: LXQt
Date: Tue Jul 14 00:00:29 2020
InstallationDate: Installed on 2020-06-12 (31 days ago)
InstallationMedia: Lubuntu 20.04 LTS "Focal Fossa" - Release amd64 (20200423)
SourcePackage: snapd
UpgradeStatus: No upgrade log present (probably fresh install)
modified.conffile..etc.sudoers.d.99-snapd.conf: [inaccessible: [Errno 13] Permission denied: '/etc/sudoers.d/99-snapd.conf']

[Olivier Tilloy (osomon)]

From duplicate bug #1887227, there's a known bug in LXDE that overrides XDG_DATA_DIRS (https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=906288), however I'm not sure where the value "/usr/share/Lubuntu" comes from. This requires further investigation.

[Hadmut Danisch (hadmut)]

It seems to come from

/etc/X11/Xsession.d/60x11-common_xdg_path

which sets

DEFAULT_XDG_DATA_DIRS='/usr/local/share/:/usr/share/'

...

if [ "$DESKTOP_SESSION" != "gnome" ]; then
     if [ -z "$XDG_DATA_DIRS" ]; then
       XDG_DATA_DIRS="$DEFAULT_XDG_DATA_DIRS"
     fi
     if [ -n "${XDG_DATA_DIRS##*/usr/share/$DESKTOP_SESSION*}" ]; then
       XDG_DATA_DIRS=/usr/share/"$DESKTOP_SESSION":"$XDG_DATA_DIRS"
      fi
     export XDG_DATA_DIRS
  fi

where $DESKTOP_SESSION has the value Lubuntu

[Launchpad Janitor (janitor)]

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

[lirel (m8r-lcodw5)]

flatpak copies this file https://github.com/flatpak/ppa-flatpak/blob/ubuntu/bionic/profile/flatpak.sh to /etc/X11/Xsession.d/20flatpack when installing.