Unblockable units or services?

[GreyGeek]

I have NO flatpak services running:

$ systemctl list-unit-files | grep flat
jerry@Aspire-V3-771:~$

Or snap services:

proc-sys-fs-binfmt_misc.mount              disabled        enabled      
snap-chromium-1100.mount                   disabled        enabled      
snap-chromium-1105.mount                   disabled        enabled      
snap-core-8689.mount                       disabled        enabled      
snap-core-8935.mount                       disabled        enabled      
snap-core18-1668.mount                     disabled        enabled      
snap-core18-1705.mount                     disabled        enabled      
snap-gnome\x2d3\x2d28\x2d1804-116.mount    disabled        enabled      
snap-gtk\x2dcommon\x2dthemes-1474.mount    disabled        enabled      
snap-gtk\x2dcommon\x2dthemes-1502.mount    disabled        enabled      
snap-snap\x2dstore-209.mount               disabled        enabled      
snap-snapd-6434.mount                      disabled        enabled      
snap-snapd-6953.mount                      disabled        enabled      
...                        
snapd.apparmor.service                     masked          enabled      
snapd.autoimport.service                   masked          enabled      
snapd.core-fixup.service                   masked          enabled      
snapd.recovery-chooser-trigger.service     masked          enabled      
snapd.seeded.service                       masked          enabled      
snapd.service                              masked          enabled      
snapd.system-shutdown.service              masked          enabled      
sudo.service                               masked          enabled      
...     
snapd.socket                               masked          enabled      
snapd.snap-repair.timer                    masked          enabled

YET,journalctl shows:

Feb 10 13:16:59 Aspire-V3-771 systemd[1685]: Starting flatpak document portal service...
...
Feb 10 13:16:59 Aspire-V3-771 systemd[1685]: Starting sandboxed app permission store...
Feb 10 13:16:59 Aspire-V3-771 dbus-daemon[1718]: [session uid=1000 pid=1718] Successfully activated service 'org.freedesktop.impl.portal.PermissionStore'
Feb 10 13:16:59 Aspire-V3-771 systemd[1685]: Started sandboxed app permission store.
...
Feb 10 13:16:59 Aspire-V3-771 systemd[1685]: Started flatpak document portal service.
Feb 10 13:16:59 Aspire-V3-771 systemd[1685]: tmp-snap.rootfs_hGokQt.mount: Succeeded.
...
Feb 10 13:17:13 Aspire-V3-771 dbus-daemon[1718]: [session uid=1000 pid=1718] Successfully activated service 'io.snapcraft.Settings'
Feb 10 13:17:13 Aspire-V3-771 io.snapcraft.Settings[2639]: userd.go:98: Starting snap userd

Later...
Feb 10 22:05:01 Aspire-V3-771 systemd[1685]: Stopped flatpak document portal service.
...
Feb 11 11:48:08 Aspire-V3-771 systemd[1795]: Listening on REST API socket for snapd user session agent.

io.snapcraft.Settings and flatpak services can be started and stopped at will? (Not my will)

[kubicle]

io.snapcraft.Settings and flatpak services can be started and stopped at will? (Not my will)

These services are probably started by xdg-desktop-portal (https://launchpad.net/ubuntu/bionic/...desktop-portal)
See: /usr/lib/systemd/user/xdg-*.service

Randomly disabling systemd services is not a good idea, if you have snaps (or flatpaks) you should let them run.
If you don't want snap services (or apps), purge snapd.

[jglen490]

If someone, like GreyGeek and others, has already purged snapd, why would the service even start at all? There shouldn't be any triggers to start the service, unless there's a timer or an external trigger.

I, for one, am deeply concerned because when I return to 20.04 LTS, I wish very much to avoid snaps and flatpaks, even inadvertent occurrences.

[kubicle]

If someone, like GreyGeek and others, has already purged snapd,

I'm fairly sure he hasn't. These service should only start when needed (when snaps call for them)...they don't run on my end, and I don't have snaps/flatpaks installed (or snapd).

[GreyGeek]

I'm fairly sure he hasn't. These service should only start when needed (when snaps call for them)...they don't run on my end, and I don't have snaps/flatpaks installed (or snapd).

To my knowledge flatpak was never installed, and it is currently not on my system.
I have uninstalled snapd & Chromium and unmounted all the loops related to them, as you can see from my "mount" command:

jerry@Aspire-V3-771:~$ mount
sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,relatime)
proc on /proc type proc (rw,nosuid,nodev,noexec,relatime)
udev on /dev type devtmpfs (rw,nosuid,noexec,relatime,size=8066244k,nr_inodes=2016561,mode=755)
devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000)
tmpfs on /run type tmpfs (rw,nosuid,nodev,noexec,relatime,size=1623420k,mode=755)
/dev/sda1 on / type btrfs (rw,relatime,ssd,space_cache,subvolid=485,subvol=/@)
securityfs on /sys/kernel/security type securityfs (rw,nosuid,nodev,noexec,relatime)
tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev)
tmpfs on /run/lock type tmpfs (rw,nosuid,nodev,noexec,relatime,size=5120k)
tmpfs on /sys/fs/cgroup type tmpfs (ro,nosuid,nodev,noexec,mode=755)
cgroup2 on /sys/fs/cgroup/unified type cgroup2 (rw,nosuid,nodev,noexec,relatime,nsdelegate)
cgroup on /sys/fs/cgroup/systemd type cgroup (rw,nosuid,nodev,noexec,relatime,xattr,name=systemd)
[B]pstore on /sys/fs/pstore[/B] type pstore (rw,nosuid,nodev,noexec,relatime)
none on /sys/fs/bpf type bpf (rw,nosuid,nodev,noexec,relatime,mode=700)
cgroup on /sys/fs/cgroup/freezer type cgroup (rw,nosuid,nodev,noexec,relatime,freezer)
cgroup on /sys/fs/cgroup/pids type cgroup (rw,nosuid,nodev,noexec,relatime,pids)
cgroup on /sys/fs/cgroup/perf_event type cgroup (rw,nosuid,nodev,noexec,relatime,perf_event)
cgroup on /sys/fs/cgroup/memory type cgroup (rw,nosuid,nodev,noexec,relatime,memory)
cgroup on /sys/fs/cgroup/hugetlb type cgroup (rw,nosuid,nodev,noexec,relatime,hugetlb)
cgroup on /sys/fs/cgroup/devices type cgroup (rw,nosuid,nodev,noexec,relatime,devices)
cgroup on /sys/fs/cgroup/blkio type cgroup (rw,nosuid,nodev,noexec,relatime,blkio)
cgroup on /sys/fs/cgroup/net_cls,net_prio type cgroup (rw,nosuid,nodev,noexec,relatime,net_cls,net_prio)
cgroup on /sys/fs/cgroup/cpuset type cgroup (rw,nosuid,nodev,noexec,relatime,cpuset)
cgroup on /sys/fs/cgroup/rdma type cgroup (rw,nosuid,nodev,noexec,relatime,rdma)
cgroup on /sys/fs/cgroup/cpu,cpuacct type cgroup (rw,nosuid,nodev,noexec,relatime,cpu,cpuacct)
systemd-1 on /proc/sys/fs/binfmt_misc type autofs (rw,relatime,fd=28,pgrp=1,timeout=0,minproto=5,maxproto=5,direct,pipe_ino=20086)
mqueue on /dev/mqueue type mqueue (rw,nosuid,nodev,noexec,relatime)
hugetlbfs on /dev/hugepages type hugetlbfs (rw,relatime,pagesize=2M)
debugfs on /sys/kernel/debug type debugfs (rw,nosuid,nodev,noexec,relatime)
tracefs on /sys/kernel/tracing type tracefs (rw,nosuid,nodev,noexec,relatime)
fusectl on /sys/fs/fuse/connections type fusectl (rw,nosuid,nodev,noexec,relatime)
configfs on /sys/kernel/config type configfs (rw,nosuid,nodev,noexec,relatime)
/dev/sda1 on /home type btrfs (rw,relatime,ssd,space_cache,subvolid=486,subvol=/@home)
binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw,nosuid,nodev,noexec,relatime)
tmpfs on /run/user/1000 type tmpfs (rw,nosuid,nodev,relatime,size=1623416k,mode=700,uid=1000,gid=1000)

which shows NO loop devices, no tmp-snap.rootfs mount, and I had previously disabled or masked all units, services & timers that relate to snap or flatpak. (I did notice "pstore on /sys/fs/pstore " and it will be disposed of shortly)

Having done that I am at loss to explain how

Starting flatpak document portal service...
Starting sandboxed app permission store...
tmp-snap.rootfs_hGokQt.mount: Succeeded.
Successfully activated service 'io.snapcraft.Settings'
io.snapcraft.Settings[2639]: userd.go:98: Starting snap userd

the above services are even starting.
"snap userd"?
"io.snapcraft.Settings"?
"tmp-snap.rootfs_hGokQt.mount"? (how can it NOT show in the mount command unless it is deliberately hidden?)

It smells of telemetry that can't be easily detected (or removed?).

[kyonides]

I know kubicle is right this time, GG. (I know he's burning to say he's always right. :P )
I also thought I had uninstalled, not purged, all snap related stuff (including everything related to Discover) and I was still able to find snapd services.
Only after I purged snapd as kubicle suggested in the post above, I stopped finding them while running the systemctl list-unit-files | grep snapd command.

[GreyGeek]

I know kubicle is right this time, GG. (I know he's burning to say he's always right. :P )
I also thought I had uninstalled, not purged, all snap related stuff (including everything related to Discover) and I was still able to find snapd services.
Only after I purged snapd as kubicle suggested in the post above, I stopped finding them while running the systemctl list-unit-files | grep snapd command.

I did that as well, and reported it in this post, and a few following it.

So, I never considered that "something" must have reinstalled snapd. So, to check, I did:
$ locate snapd, and there they were, all which I had painstakingly removed....

/etc/apparmor.d/usr.lib.snapd.snap-confine.real
/etc/apparmor.d/local/usr.lib.snapd.snap-confine.real
/etc/apt/apt.conf.d/20snapd.conf
/etc/sudoers.d/99-snapd.conf
/etc/systemd/system/snap-snapd-6434.mount
/etc/systemd/system/snap-snapd-6953.mount
/etc/systemd/system/snapd.apparmor.service
/etc/systemd/system/snapd.autoimport.service
/etc/systemd/system/snapd.core-fixup.service
/etc/systemd/system/snapd.recovery-chooser-trigger.service
/etc/systemd/system/snapd.seeded.service
/etc/systemd/system/snapd.service
/etc/systemd/system/snapd.snap-repair.timer
/etc/systemd/system/snapd.socket
/etc/systemd/system/snapd.system-shutdown.service
/etc/systemd/system/cloud-final.service.wants/snapd.seeded.service
/etc/systemd/system/final.target.wants/snapd.system-shutdown.service
/etc/systemd/system/multi-user.target.wants/snapd.autoimport.service
/etc/systemd/system/multi-user.target.wants/snapd.core-fixup.service
/etc/systemd/system/multi-user.target.wants/snapd.recovery-chooser-trigger.service
/etc/systemd/system/multi-user.target.wants/snapd.seeded.service
/etc/systemd/system/timers.target.wants/snapd.snap-repair.timer
/etc/udev/rules.d/70-snap.snapd.rules
/home/jerry/Documents/snapd_depends_rdepends.txt
/snap/snapd
/snap/snapd/6434
/snap/snapd/6953
/snap/snapd/current
/usr/lib/x86_64-linux-gnu/libsnapd-glib.so.1
/usr/lib/x86_64-linux-gnu/libsnapd-glib.so.1.0.0
/usr/share/doc/libsnapd-glib1
/usr/share/doc/libsnapd-glib1/changelog.Debian.gz
/usr/share/doc/libsnapd-glib1/copyright
/var/cache/snapd
/var/cache/snapd/aux
/var/cache/snapd/commands.db
/var/cache/snapd/names
/var/cache/snapd/sections
/var/cache/snapd/aux/99T7MUlRhtI3U0QFgl5mXXESAiSwt776.json
...
/var/cache/snapd/aux/jZLfBRzf1cYlYysIjD2bwSzNtngY0qit.json
/var/lib/snapd
/var/lib/dpkg/info/libsnapd-glib1:amd64.list
/var/lib/dpkg/info/libsnapd-glib1:amd64.md5sums
/var/lib/dpkg/info/libsnapd-glib1:amd64.shlibs
/var/lib/dpkg/info/libsnapd-glib1:amd64.symbols
/var/lib/dpkg/info/libsnapd-glib1:amd64.triggers
/var/lib/dpkg/info/snapd.list
/var/lib/dpkg/info/snapd.postrm
/var/lib/snapd/apparmor
/var/lib/snapd/assertions
/var/lib/snapd/cache
/var/lib/snapd/cookie
/var/lib/snapd/desktop
/var/lib/snapd/device
/var/lib/snapd/features
/var/lib/snapd/hostfs
/var/lib/snapd/mount
/var/lib/snapd/seccomp
/var/lib/snapd/sequence
/var/lib/snapd/snaps
/var/lib/snapd/snapshots
/var/lib/snapd/state.json
/var/lib/snapd/system-key
/var/lib/snapd/apparmor/profiles
/var/lib/snapd/apparmor/profiles/snap-confine.core.8935
/var/lib/snapd/apparmor/profiles/snap-confine.snapd.6953
/var/lib/snapd/apparmor/profiles/snap-update-ns.chromium
/var/lib/snapd/apparmor/profiles/snap-update-ns.core
/var/lib/snapd/apparmor/profiles/snap-update-ns.snap-store
/var/lib/snapd/apparmor/profiles/snap.chromium.chromedriver
/var/lib/snapd/apparmor/profiles/snap.chromium.chromium
/var/lib/snapd/apparmor/profiles/snap.core.hook.configure
/var/lib/snapd/apparmor/profiles/snap.snap-store.snap-store
/var/lib/snapd/assertions/asserts-v0
/var/lib/snapd/assertions/private-keys-v1
/var/lib/snapd/assertions/asserts-v0/account-key
/var/lib/snapd/assertions/asserts-v0/model
/var/lib/snapd/assertions/asserts-v0/serial
/var/lib/snapd/assertions/asserts-v0/snap-declaration
/var/lib/snapd/assertions/asserts-v0/snap-revision
/var/lib/snapd/assertions/asserts-v0/account-key/BWDEoaqyr25nF5SNCvEv2v7QnM9QsfCc0PBMYD_i2NGSQ32EF2d4D0hqUel3m8ul
/var/lib/snapd/assertions/asserts-v0/account-key/wrfougkz3Huq2T_KklfnufCC0HzG7bJ9wP99GV0FF-D3QH3eJtuSRlQc2JhrAoh1
/var/lib/snapd/assertions/asserts-v0/account-key/BWDEoaqyr25nF5SNCvEv2v7QnM9QsfCc0PBMYD_i2NGSQ32EF2d4D0hqUel3m8ul/active
/var/lib/snapd/assertions/asserts-v0/account-key/wrfougkz3Huq2T_KklfnufCC0HzG7bJ9wP99GV0FF-D3QH3eJtuSRlQc2JhrAoh1/active
/var/lib/snapd/assertions/asserts-v0/model/16
/var/lib/snapd/assertions/asserts-v0/model/16/generic
/var/lib/snapd/assertions/asserts-v0/model/16/generic/generic-classic
/var/lib/snapd/assertions/asserts-v0/model/16/generic/generic-classic/active
/var/lib/snapd/assertions/asserts-v0/serial/generic
/var/lib/snapd/assertions/asserts-v0/serial/generic/generic-classic
/var/lib/snapd/assertions/asserts-v0/serial/generic/generic-classic/ecfde1a2-353f-47f7-a598-20ba4a4b0108
/var/lib/snapd/assertions/asserts-v0/serial/generic/generic-classic/ecfde1a2-353f-47f7-a598-20ba4a4b0108/active
/var/lib/snapd/assertions/asserts-v0/snap-declaration/16
/var/lib/snapd/assertions/asserts-v0/snap-declaration/16/99T7MUlRhtI3U0QFgl5mXXESAiSwt776
...
/var/lib/snapd/assertions/asserts-v0/snap-declaration/16/jZLfBRzf1cYlYysIjD2bwSzNtngY0qit/active.2
/var/lib/snapd/assertions/asserts-v0/snap-revision/-_mfpDEpI3dsbKjj_NJxmooIl1bSEU_d5px7aCmE5RNOyGuT0MF0kQbBsgjX54s8
...
/wxnTbtFZHQUtTfqzYLAB39MjPjfRJmHux1nirVt08S_tLqTggRteX2OW5IMoMGZs/active
/var/lib/snapd/desktop/applications
/var/lib/snapd/desktop/icons
/var/lib/snapd/desktop/applications/chromium_chromium.desktop
/var/lib/snapd/desktop/applications/mimeinfo.cache
/var/lib/snapd/desktop/applications/snap-store_snap-store.desktop
/var/lib/snapd/device/private-keys-v1
/var/lib/snapd/device/private-keys-v1/MG6Dyy5bmNxce18qkzlEmJ7s3-s3k9fs3Xe0b8GuRQDU1gPzfBu8W5VOQy9fqdPb
/var/lib/snapd/mount/snap.chromium.fstab
/var/lib/snapd/mount/snap.chromium.user-fstab
/var/lib/snapd/mount/snap.snap-store.fstab
/var/lib/snapd/mount/snap.snap-store.user-fstab
/var/lib/snapd/seccomp/bpf
/var/lib/snapd/seccomp/bpf/global.bin
/var/lib/snapd/seccomp/bpf/snap.chromium.chromedriver.bin
/var/lib/snapd/seccomp/bpf/snap.chromium.chromedriver.src
/var/lib/snapd/seccomp/bpf/snap.chromium.chromium.bin
/var/lib/snapd/seccomp/bpf/snap.chromium.chromium.src
/var/lib/snapd/seccomp/bpf/snap.core.hook.configure.bin
/var/lib/snapd/seccomp/bpf/snap.core.hook.configure.src
/var/lib/snapd/seccomp/bpf/snap.snap-store.snap-store.bin
/var/lib/snapd/seccomp/bpf/snap.snap-store.snap-store.src
/var/lib/snapd/sequence/chromium.json
/var/lib/snapd/sequence/core.json
/var/lib/snapd/sequence/core18.json
/var/lib/snapd/sequence/gnome-3-28-1804.json
/var/lib/snapd/sequence/gtk-common-themes.json
/var/lib/snapd/sequence/microk8s.json
/var/lib/snapd/sequence/snap-store.json
/var/lib/snapd/sequence/snapd.json
/var/lib/snapd/snaps/chromium_1100.snap
/var/lib/snapd/snaps/chromium_1105.snap
/var/lib/snapd/snaps/core18_1668.snap
/var/lib/snapd/snaps/core18_1705.snap
/var/lib/snapd/snaps/core_8689.snap
/var/lib/snapd/snaps/core_8935.snap
/var/lib/snapd/snaps/gnome-3-28-1804_116.snap
/var/lib/snapd/snaps/gtk-common-themes_1474.snap
/var/lib/snapd/snaps/gtk-common-themes_1502.snap
/var/lib/snapd/snaps/snap-store_209.snap
/var/lib/snapd/snaps/snapd_6434.snap
/var/lib/snapd/snaps/snapd_6953.snap
/var/lib/systemd/deb-systemd-helper-enabled/snapd.apparmor.service.dsh-also
/var/lib/systemd/deb-systemd-helper-enabled/snapd.autoimport.service.dsh-also
/var/lib/systemd/deb-systemd-helper-enabled/snapd.core-fixup.service.dsh-also
/var/lib/systemd/deb-systemd-helper-enabled/snapd.recovery-chooser-trigger.service.dsh-also
/var/lib/systemd/deb-systemd-helper-enabled/snapd.seeded.service.dsh-also
/var/lib/systemd/deb-systemd-helper-enabled/snapd.service.dsh-also
/var/lib/systemd/deb-systemd-helper-enabled/snapd.snap-repair.timer.dsh-also
/var/lib/systemd/deb-systemd-helper-enabled/snapd.socket.dsh-also
/var/lib/systemd/deb-systemd-helper-enabled/snapd.system-shutdown.service.dsh-also
/var/lib/systemd/deb-systemd-helper-enabled/cloud-final.service.wants/snapd.seeded.service
/var/lib/systemd/deb-systemd-helper-enabled/final.target.wants/snapd.system-shutdown.service
/var/lib/systemd/deb-systemd-helper-enabled/multi-user.target.wants/snapd.apparmor.service
/var/lib/systemd/deb-systemd-helper-enabled/multi-user.target.wants/snapd.autoimport.service
/var/lib/systemd/deb-systemd-helper-enabled/multi-user.target.wants/snapd.core-fixup.service
/var/lib/systemd/deb-systemd-helper-enabled/multi-user.target.wants/snapd.recovery-chooser-trigger.service
/var/lib/systemd/deb-systemd-helper-enabled/multi-user.target.wants/snapd.seeded.service
/var/lib/systemd/deb-systemd-helper-enabled/multi-user.target.wants/snapd.service
/var/lib/systemd/deb-systemd-helper-enabled/sockets.target.wants/snapd.socket
/var/lib/systemd/deb-systemd-helper-enabled/timers.target.wants/snapd.snap-repair.timer
/var/lib/systemd/deb-systemd-helper-masked/snapd.apparmor.service
/var/lib/systemd/deb-systemd-helper-masked/snapd.autoimport.service
/var/lib/systemd/deb-systemd-helper-masked/snapd.core-fixup.service
/var/lib/systemd/deb-systemd-helper-masked/snapd.recovery-chooser-trigger.service
/var/lib/systemd/deb-systemd-helper-masked/snapd.snap-repair.timer
/var/lib/systemd/deb-systemd-helper-masked/snapd.socket
/var/lib/systemd/deb-systemd-helper-masked/snapd.system-shutdown.service
/var/snap/snapd
/var/snap/snapd/6434
/var/snap/snapd/6953
/var/snap/snapd/common
/var/snap/snapd/current

So, I immediately ran this
$ sudo apt purge snapd

... 
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following packages will be REMOVED:
  snapd*
0 upgraded, 0 newly installed, 1 to remove and 2 not upgraded.
After this operation, 0 B of additional disk space will be used.
Do you want to continue? [Y/n] 
(Reading database ... 351121 files and directories currently installed.)
Purging configuration files for snapd (2.44.3+20.04) ...
Stopping snap-chromium-1100.mount
Stopping unit snap-chromium-1100.mount
Waiting until unit snap-chromium-1100.mount is stopped [attempt 1]
snap-chromium-1100.mount is stopped.
Removing snap chromium and revision 1100
[B]Removing snap-chromium-1100.mount[/B]
Stopping snap-chromium-1105.mount
Stopping unit snap-chromium-1105.mount
Waiting until unit snap-chromium-1105.mount is stopped [attempt 1]
snap-chromium-1105.mount is stopped.
Removing snap chromium and revision 1105
[B]Removing snap-chromium-1105.mount[/B]
Stopping snap-core-8689.mount
Stopping unit snap-core-8689.mount
Waiting until unit snap-core-8689.mount is stopped [attempt 1]
snap-core-8689.mount is stopped.
Removing snap core and revision 8689
[B]Removing snap-core-8689.mount[/B]
Stopping snap-core-8935.mount
Stopping unit snap-core-8935.mount
Waiting until unit snap-core-8935.mount is stopped [attempt 1]
snap-core-8935.mount is stopped.
Removing snap core and revision 8935
[B]Removing snap-core-8935.mount[/B]
Stopping snap-core18-1668.mount
Stopping unit snap-core18-1668.mount
Waiting until unit snap-core18-1668.mount is stopped [attempt 1]
snap-core18-1668.mount is stopped.
Removing snap core18 and revision 1668
[B]Removing snap-core18-1668.mount[/B]
Stopping snap-core18-1705.mount
Stopping unit snap-core18-1705.mount
Waiting until unit snap-core18-1705.mount is stopped [attempt 1]
snap-core18-1705.mount is stopped.
Removing snap core18 and revision 1705
[B]Removing snap-core18-1705.mount[/B]
Stopping snap-gnome\x2d3\x2d28\x2d1804-116.mount
Stopping unit snap-gnome\x2d3\x2d28\x2d1804-116.mount
Waiting until unit snap-gnome\x2d3\x2d28\x2d1804-116.mount is stopped [attempt 1]
snap-gnome\x2d3\x2d28\x2d1804-116.mount is stopped.
Removing snap gnome-3-28-1804 and revision 116
[B]Removing snap-gnome\x2d3\x2d28\x2d1804-116.mount[/B]
Stopping snap-gtk\x2dcommon\x2dthemes-1474.mount
Stopping unit snap-gtk\x2dcommon\x2dthemes-1474.mount
Waiting until unit snap-gtk\x2dcommon\x2dthemes-1474.mount is stopped [attempt 1]
snap-gtk\x2dcommon\x2dthemes-1474.mount is stopped.
Removing snap gtk-common-themes and revision 1474
Removing [B]snap-gtk\x2dcommon\x2dthemes-1474.mount[/B]
Stopping snap-gtk\x2dcommon\x2dthemes-1502.mount
Stopping unit snap-gtk\x2dcommon\x2dthemes-1502.mount
Waiting until unit snap-gtk\x2dcommon\x2dthemes-1502.mount is stopped [attempt 1]
snap-gtk\x2dcommon\x2dthemes-1502.mount is stopped.
Removing snap gtk-common-themes and revision 1502
Removing[B] snap-gtk\x2dcommon\x2dthemes-1502.mount[/B]
Stopping snap-snap\x2dstore-209.mount
Stopping unit snap-snap\x2dstore-209.mount
Waiting until unit snap-snap\x2dstore-209.mount is stopped [attempt 1]
snap-snap\x2dstore-209.mount is stopped.
Removing snap snap-store and revision 209
Removing [B]snap-snap\x2dstore-209.mount[/B]
Stopping snap-snapd-6434.mount
Stopping unit snap-snapd-6434.mount
Waiting until unit snap-snapd-6434.mount is stopped [attempt 1]
snap-snapd-6434.mount is stopped.
Removing snap snapd and revision 6434
Removing [B]snap-snapd-6434.mount[/B]
Stopping snap-snapd-6953.mount
Stopping unit snap-snapd-6953.mount
Waiting until unit snap-snapd-6953.mount is stopped [attempt 1]
snap-snapd-6953.mount is stopped.
Removing snap snapd and revision 6953
Removing [B]snap-snapd-6953.mount[/B]
Final directory cleanup
Discarding preserved snap namespaces
Removing extra snap-confine apparmor rules
Removing snapd cache
Removing snapd state
:~$

In a listing above I showed the results of the mount command. NONE of the mount points I've highlighted above, which I had previously removed manually, appeared in that mount listing.

I do not know what triggered snapd to be reinstalled. I suspect it is an automatic update. If so, I am going to turn those off and manually check them before I allow them to be installed.

[jglen490]

If snapd is being reinstalled after being purged, that's a foul. But, to be sure, maybe run

sudo apt autoremove
sudo apt autoclean
sudo apt clean

after the purge. And, if it's still can be reinstalled, that's a really bad foul, and kind of disrespectful to the user and Linux.

[kubicle]

It smells of telemetry that can't be easily detected (or removed?).

It's not telemetry. snaps/flatpaks are sandboxed and can't, by default, access things outside their sandbox.The xdg-portal services provide the framework to allow them to reach out from their sandbox (for things like opening files outside their sandbox, networking, printing, desktop notifications etc.).

I know kubicle is right this time, GG. (I know he's burning to say he's always right. :P )

I'm obviously not always right, I'm just never wrong and never make mitsakes...dang it

I do not know what triggered snapd to be reinstalled. I suspect it is an automatic update. If so, I am going to turn those off and manually check them before I allow them to be installed.

This shouldn't be terribly difficult to figure out. You can first check dpkg-logs to see the date/time it was installed:

[FONT=monospace][COLOR=#18B218]zgrep[/COLOR] snapd:amd64 [COLOR=#1818B2]/var/log/dpkg.log*[/COLOR] | [COLOR=#18B218]grep[/COLOR] installed[/FONT]

(using zgrep because logrotate compresses older logs...feel free to post the output here if you have trouble deciphering it)
You can then check the install date/time on the correct /var/log/apt/history.log.* to see what was going on.

There is a chance a package you installed/upgraded recommends snapd, and it was installed with it as a recommended package (if your apt is configured to treat recommends as dependencies, which is the default in *buntus). Recommends aren't hard dependencies so you can remove/purge them afterwards without removing the package that recommended them (you can also configure apt to not treat recommends as dependencies).

[GreyGeek]

Never heard of zgrep. Interesting command.
$ zgrep snapd:amd64 /var/log/dpkg.log* | grep installed

/var/log/dpkg.log:2020-05-11 19:35:36 status not-installed snapd:amd64 <none>
/var/log/dpkg.log.1:2020-04-04 20:35:44 status half-installed snapd:amd64 2.44+20.04
[COLOR=#ff0000]/var/log/dpkg.log.1:2020-04-04 20:36:04 status installed snapd:amd64 2.44.2+20.04[/COLOR]
/var/log/dpkg.log.1:2020-04-14 15:56:10 status half-installed snapd:amd64 2.44.2+20.04
[B]/var/log/dpkg.log.1:2020-04-14 15:57:00 status installed snapd:amd64 2.44.3+20.04
/var/log/dpkg.log.1:2020-04-20 16:04:53 status installed snapd:amd64 2.44.3+20.04[/B]
/var/log/dpkg.log.1:2020-04-20 16:04:54 status half-installed snapd:amd64 2.44.3+20.04
/var/log/dpkg.log.2.gz:2020-03-18 12:14:32 status half-installed snapd:amd64 2.44~pre1+20.04
[B]/var/log/dpkg.log.2.gz:2020-03-18 12:14:51 status installed snapd:amd64 2.44+20.04[/B]
/var/log/dpkg.log.3.gz:2020-02-17 12:21:47 status half-installed snapd:amd64 2.43~pre1+20.04
[B]/var/log/dpkg.log.3.gz:2020-02-17 12:21:55 status installed snapd:amd64 2.43.3+git1.8109f8[/B]
/var/log/dpkg.log.3.gz:2020-02-26 21:40:01 status half-installed snapd:amd64 2.43.3+git1.8109f8
[B]/var/log/dpkg.log.3.gz:2020-02-26 21:40:08 status installed snapd:amd64 2.44~pre1+20.04[/B]
/var/log/dpkg.log.4.gz:2020-01-04 05:18:45 status half-installed snapd:amd64 2.42.1+20.04
[B]/var/log/dpkg.log.4.gz:2020-01-04 05:19:36 status installed snapd:amd64 2.42.1+20.04[/B]
/var/log/dpkg.log.4.gz:2020-01-16 12:16:41 status half-installed snapd:amd64 2.42.1+20.04
[B]/var/log/dpkg.log.4.gz:2020-01-16 12:19:23 status installed snapd:amd64 2.43~pre1+20.04[/B]
jerry@Aspire-V3-771:~$

It was installed several times, the most recently about 1 month ago.

2020-04-04 20:35:48 configure kdeconnect:amd64 1.4-0ubuntu4 <none>
2020-04-04 20:35:48 status unpacked kdeconnect:amd64 1.4-0ubuntu4
2020-04-04 20:35:48 status half-configured kdeconnect:amd64 1.4-0ubuntu4
2020-04-04 20:35:48 status installed kdeconnect:amd64 1.4-0ubuntu4
2020-04-04 20:35:48 configure apparmor:amd64 2.13.3-7ubuntu3 <none>
2020-04-04 20:35:48 status unpacked apparmor:amd64 2.13.3-7ubuntu3
2020-04-04 20:35:48 status half-configured apparmor:amd64 2.13.3-7ubuntu3
2020-04-04 20:36:00 status installed apparmor:amd64 2.13.3-7ubuntu3
2020-04-04 20:36:00 configure python3-cssselect:all 1.1.0-2 <none>
2020-04-04 20:36:00 status unpacked python3-cssselect:all 1.1.0-2
2020-04-04 20:36:00 status half-configured python3-cssselect:all 1.1.0-2
2020-04-04 20:36:00 status installed python3-cssselect:all 1.1.0-2
2020-04-04 20:36:00 configure snapd:amd64 2.44.2+20.04 <none>
2020-04-04 20:36:00 status unpacked snapd:amd64 2.44.2+20.04
2020-04-04 20:36:00 status half-configured snapd:amd64 2.44.2+20.04
2020-04-04 20:36:04 status installed snapd:amd64 2.44.2+20.04
2020-04-04 20:36:04 trigproc mime-support:all 3.64ubuntu1 <none>
2020-04-04 20:36:04 status half-configured mime-support:all 3.64ubuntu1
2020-04-04 20:36:05 status installed mime-support:all 3.64ubuntu1
2020-04-04 20:36:05 trigproc hicolor-icon-theme:all 0.17-2 <none>
2020-04-04 20:36:05 status half-configured hicolor-icon-theme:all 0.17-2
2020-04-04 20:36:05 status installed hicolor-icon-theme:all 0.17-2
2020-04-04 20:36:05 trigproc libc-bin:amd64 2.31-0ubuntu6 <none>

And the winner is ... apparmor!

$ sudo apt-cache rdepends apparmor

apparmor
Reverse Depends:
  ioquake3
  libreoffice-common
  libreoffice-common
  rtcw
  unbound
  torbrowser-launcher
  telepathy-mission-control-5
  surf
  pollen
  openntpd
  ntpsec
  mosquitto
  lightdm-remote-session-x2go
  lightdm-remote-session-freerdp2
  apparmor-profiles-extra
  i2p-router
  i2p
  haveged
  ejabberd
  docker.io
  dhcpcanon
 [COLOR=#ff0000][B] snapd[/B][/COLOR]
  ubuntu-standard
  tcpdump
  sssd-common
  squid
  rsyslog
  libreoffice-common
  man-db
  libvirt-daemon-system
  libreoffice-common
  libmutter-6-0
  apparmor-profiles
  gpsd
  clamav-freshclam
  clamav-daemon
  apparmor-utils

So, I guess after every update I'll automatically do a purge of snapd. If it's not present, no harm, no foul.

[kubicle]

Never heard of zgrep. Interesting command.
$ zgrep snapd:amd64 /var/log/dpkg.log* | grep installed

/var/log/dpkg.log:2020-05-11 19:35:36 status not-installed snapd:amd64 <none>
/var/log/dpkg.log.1:2020-04-04 20:35:44 status half-installed snapd:amd64 2.44+20.04
[COLOR=#ff0000]/var/log/dpkg.log.1:2020-04-04 20:36:04 status installed snapd:amd64 2.44.2+20.04[/COLOR]
/var/log/dpkg.log.1:2020-04-14 15:56:10 status half-installed snapd:amd64 2.44.2+20.04
[B]/var/log/dpkg.log.1:2020-04-14 15:57:00 status installed snapd:amd64 2.44.3+20.04
/var/log/dpkg.log.1:2020-04-20 16:04:53 status installed snapd:amd64 2.44.3+20.04[/B]
/var/log/dpkg.log.1:2020-04-20 16:04:54 status half-installed snapd:amd64 2.44.3+20.04
/var/log/dpkg.log.2.gz:2020-03-18 12:14:32 status half-installed snapd:amd64 2.44~pre1+20.04
[B]/var/log/dpkg.log.2.gz:2020-03-18 12:14:51 status installed snapd:amd64 2.44+20.04[/B]
/var/log/dpkg.log.3.gz:2020-02-17 12:21:47 status half-installed snapd:amd64 2.43~pre1+20.04
[B]/var/log/dpkg.log.3.gz:2020-02-17 12:21:55 status installed snapd:amd64 2.43.3+git1.8109f8[/B]
/var/log/dpkg.log.3.gz:2020-02-26 21:40:01 status half-installed snapd:amd64 2.43.3+git1.8109f8
[B]/var/log/dpkg.log.3.gz:2020-02-26 21:40:08 status installed snapd:amd64 2.44~pre1+20.04[/B]
/var/log/dpkg.log.4.gz:2020-01-04 05:18:45 status half-installed snapd:amd64 2.42.1+20.04
[B]/var/log/dpkg.log.4.gz:2020-01-04 05:19:36 status installed snapd:amd64 2.42.1+20.04[/B]
/var/log/dpkg.log.4.gz:2020-01-16 12:16:41 status half-installed snapd:amd64 2.42.1+20.04
[B]/var/log/dpkg.log.4.gz:2020-01-16 12:19:23 status installed snapd:amd64 2.43~pre1+20.04[/B]
jerry@Aspire-V3-771:~$

It was installed several times, the most recently about 1 month ago.

dpkg.logs show upgrades (of snapd) as well as new installs, what you want to look at is the first time it was installed (/var/log/dpkg.log.4.gz:2020-01-04 05:19:36 status installed snapd:amd64 2.42.1+20.04).
Check the /var/log/apt/history.log* for January to see what was installed at around 5am 4th January. (snapd has been installed since then, and only recently removed/purged: /var/log/dpkg.log:2020-05-11 19:35:36 status not-installed snapd:amd64 <none>)
[Is that possibly the time you upgraded to focal?]
EDIT: read the logs wrong, the first install was 4th Jan, not 16th Jan

And the winner is ... apparmor!

$ sudo apt-cache rdepends apparmor

apparmor
Reverse Depends:
ioquake3
libreoffice-common
libreoffice-common
rtcw
unbound
torbrowser-launcher
telepathy-mission-control-5
surf
pollen
openntpd
ntpsec
mosquitto
lightdm-remote-session-x2go
lightdm-remote-session-freerdp2
apparmor-profiles-extra
i2p-router
i2p
haveged
ejabberd
docker.io
dhcpcanon
[COLOR=#ff0000][B] snapd[/B][/COLOR]
ubuntu-standard
tcpdump
sssd-common
squid
rsyslog
libreoffice-common
man-db
libvirt-daemon-system
libreoffice-common
libmutter-6-0
apparmor-profiles
gpsd
clamav-freshclam
clamav-daemon
apparmor-utils

So, I guess after every update I'll automatically do a purge of snapd. If it's not present, no harm, no foul.

It's the other way around (rdepends = reverse depends), snapd depends on apparmor. Apparmor does not pull in snapd.

[oshunluvr]

Ok, now I'm interested. I purged snapd on May 1st after removing the 3 snaps I had been using (I found alternatives instead) because snap was taking 1/3 of my boot time. It's still gone and no evidence it's left anything behind except

/var/lib/systemd/deb-systemd-helper-enabled/snapd.service.wants/neon-update-kf5-snap.service

I really don't want to use snap. Too much overhead. I may have to leave Chromium behind because of that...

[GreyGeek]

$ sudo apt-cache depends apparmor

apparmor
  Depends: debconf
  Depends: lsb-base
 |Depends: debconf
  Depends: <debconf-2.0>
    cdebconf
    debconf
  Depends: <python3:any>
    python3:i386
    python3
  Depends: libc6
  Breaks: apparmor-profiles-extra
  Breaks: fcitx-data
[COLOR=#ff0000][B]  Breaks: [/B][/COLOR][COLOR=#000000][B]snapd[/B][/COLOR]
  Suggests: apparmor-profiles-extra
  Suggests: apparmor-utils
  Replaces: fcitx-data

[claydoh]

https://www.debian.org/doc/debian-po...ackages-breaks

Normally a Breaks entry will have an “earlier than” version clause; such a Breaks is introduced in the version of an (implicit or explicit) dependency which violates an assumption or reveals a bug in earlier versions of the broken package, or which takes over a file from earlier versions of the package named in Breaks. This use of Breaks will inform higher-level package management tools that the broken package must be upgraded before the new one.

Package: apparmor
Architecture: any
Depends: debconf,
         lsb-base,
         ${misc:Depends},
         ${python3:Depends},
         ${shlibs:Depends}
Suggests: apparmor-profiles-extra,
          apparmor-utils
Pre-Depends: ${misc:Pre-Depends}
Breaks: apparmor-profiles-extra (<< 1.21),
        fcitx-data (<< 1:4.2.9.1-1ubuntu2),
[B]        snapd [COLOR=#ff0000](<< 2.44.3+20.04~),[/COLOR][/B]
Replaces: fcitx-data (<< 1:4.2.9.1-1ubuntu2)

[kubicle]

$ sudo apt-cache depends apparmor

apparmor
Depends: debconf
Depends: lsb-base
|Depends: debconf
Depends: <debconf-2.0>
  cdebconf
  debconf
Depends: <python3:any>
  python3:i386
  python3
Depends: libc6
Breaks: apparmor-profiles-extra
Breaks: fcitx-data
[COLOR=#ff0000][B]  Breaks: [/B][/COLOR][COLOR=#000000][B]snapd[/B][/COLOR]
Suggests: apparmor-profiles-extra
Suggests: apparmor-utils
Replaces: fcitx-data

That is "Breaks", not "Depends" or "Recommends"...this just tells apt that this version breaks (usually older versions) of particular package (so it can't be upgraded if a "breaks" version of a package is installed...it is *not* installed as a dependency if the package is not installed.)
In this case, this version of apparmor breaks versions of snapd below 2.44.3+20.04~ (even though apt-cache does not show the version) . But again, apparmor does not depend on snapd and doesn't install it automatically.

Have you already checked the apt/history.log for January like I mentioned? Check the apt run matching the date/time of when snapd was first installed and compare the list of installed/upgraded packages to the rdepends of snapd.