October 12, 2020: installation of Xubuntu 20.04 on LDLC computer Saturne SG4-I3-8-S9H7

Why I have reinstalled a new Linux version and why I have switched back to Ubuntu

• from a long time I had to do CTRL-ALT-F1 CTRL-ALT-F7 to be able to log in (the X server starts but Xfce hangs at startup, with the mouse showing a "hourglass" symbol).
• sometime in suspend or in hibernation the computer shutdowns completely (yes, even in hibernation, i.e. it restarts as it had been shutdown).
• my network card does not work all the time, sometime I am compelled to connect to my "box" using WIFI instead. It may be due to some malfunctioning of the "plugs" allowing to pass information on the apartment electrical grid.
• at each startup I am compelled to add a new mode manually for my Philips 27" screen:

  $ xrandr --newmode "2560x1440_43.00"  217.50  2560 2720 2992 3424  1440 1443 1448 1478 -hsync +vsync 
  $ xrandr --addmode HDMI-1 "2560x1440_43.00" 
  

Installation

$ update-initramfs -k all -c -v

VFS: unable to mount root fs on unknown-block(0 0)

$ update-grub

Screensaver preventing to resume from suspend

No sound at startup

$ pulseaudio -v
[…]
Home directory not accessible: Permission denied

$ sudo chown jscordi:jscordi jscordi

Hibernation

sudo dpkg-reconfigure gdm3

$ swapon -s
Filename Type Size Used Priority
/dev/dm-1 partition 9764860 0 -2
$ free -m
total used free shared buff/cache available
Mem: 7857 1805 4107 349 1944 5408
Swap: 9535 0 9535

$ systemctl hibernate 

$ sudo cat /etc/polkit-1/localauthority/50-local.d/com.ubuntu.enable-hibernate.pkla

[Re-enable hibernate by default in upower]
Identity=unix-user:*
Action=org.freedesktop.upower.hibernate
ResultActive=yes
[Re-enable hibernate by default in logind]
Identity=unix-user:*
Action=org.freedesktop.login1.hibernate;org.freedesktop.login1.handle-hibernate-key;org.freedesktop.login1;org.freedesktop.login1.hibernate-multiple-sessions;org.freedesktop.login1.hibernate-ignore-inhibit
ResultActive=yes

Hybrid Sleep is not an intermediary state between Suspension/backup to RAM ("Sleep") and that to disk ("Hibernation"), but a double operation; it simply does both.
It ensures all that is needed for the Hibernation procedure to work, but it doesn’t shut down the machine; instead, it suspends it to RAM (Sleep mode). As long as power is not completely drained, only the ’Sleep/Suspend to RAM’ capability is visible. In case of total power drain, the Hibernation capability is used: the machine is shut down but is able to restore all programs from swap upon startup.

Leafnode

Apache

Amarok

$ sudo add-apt-repository ppa:joe-yasi/amarok-kde5
$ sudo apt-get update

Tracker Gnome indexer

La raison principale qui a poussé les développeurs d’Ubuntu à amputer GNOME Shell de Tracker serait la consommation accrue d’énergie quand Tracker indexe des fichiers, ce qui impacterait sensiblement l’autonomie des batteries d’ordinateurs portables.

$ tracker --reset -r
CAUTION: This process may irreversibly delete data.
Although most content indexed by Tracker can be safely reindexed, it can’t be assured that this is the case for all data. Be aware that you may be incurring in a data loss situation, proceed at your own risk.
Are you sure you want to proceed? [y|N]: y
Found 0 PIDs…
_g_io_module_get_default: Found default implementation dconf (DConfSettingsBackend) for ‘gsettings-backend’
Setting database locations
Checking database directories exist
Checking database version
  Could not find database version file:’/home/jscordi/.cache/tracker/db-version.txt’
  Current databases are either old or no databases are set up yet
  A reindex will be forced
  Creating version file ’/home/jscordi/.cache/tracker/db-version.txt’
Checking whether database files exist
Removing all database/storage files
  Removing database:’/home/jscordi/.cache/tracker/meta.db’
  Removing db-locale file:’/home/jscordi/.cache/tracker/db-locale.txt’
  Removing journal:’/home/jscordi/.local/share/tracker/data/tracker-store.journal’
  Removing db-version file:’/home/jscordi/.cache/tracker/db-version.txt’

$ systemctl --user mask tracker-store.service tracker-miner-fs.service tracker-miner-rss.service tracker-extract.service tracker-miner-apps.service tracker-writeback.service
Unit tracker-miner-rss.service does not exist, proceeding anyway.
Unit tracker-miner-apps.service does not exist, proceeding anyway.
Created symlink /home/jscordi/.config/systemd/user/tracker-store.service → /dev/null.
Created symlink /home/jscordi/.config/systemd/user/tracker-miner-fs.service → /dev/null.
Created symlink /home/jscordi/.config/systemd/user/tracker-miner-rss.service → /dev/null.
Created symlink /home/jscordi/.config/systemd/user/tracker-extract.service → /dev/null.
Created symlink /home/jscordi/.config/systemd/user/tracker-miner-apps.service → /dev/null.
Created symlink /home/jscordi/.config/systemd/user/tracker-writeback.service → /dev/null.

You may get a warning that some of these services do not exist - ignore it. That’s because for example on Ubuntu 19.04 there’s no tracker-miner-rss.service by default, but there is one on Solus OS and Fedora, which in turn do not have tracker-miner-apps.service.

$ tracker --reset -r

$ systemctl --user unmask tracker-store.service tracker-miner-fs.service tracker-miner-rss.service tracker-extract.service tracker-miner-apps.service tracker-writeback.service

#!/bin/sh
tracker --reset -r
xrandr --newmode "2560x1440_43.00"  217.50  2560 2720 2992 3424  1440 1443 1448 1478 -hsync +vsync
xrandr --addmode HDMI-1 "2560x1440_43.00"

Thunderbird and Free pop3 server

/home/jscordi/local/non_src/thunderbird/thunderbird/thunderbird %u

Bonjour, Problème résolu. Dans l’éditeur de configuration: security.tls.version.min value = 3 --> security.tls.version.min value = 1

Qt 4 libraries for LyX 2.3.2

$ cd /home/local/jscordia/src/external_projects/lyx-2.3.2
$ ./src/lyx 
./src/lyx: error while loading shared libraries: libQtSvg.so.4: cannot open shared object file: No such file or directory

$ sudo apt-get install libqtcore4
$ sudo apt-get install libqt4-svg

Security policy for ImageMagick

out.djvu created
mogrify-im6.q16: attempt to perform an operation not allowed by the security policy ‘PDF’ @ error/constitute.c/IsCoderAuthorized/408.
Syntax Error: Document stream is empty
Syntax Error: Could not merge damaged documents (’out1.pdf’)

$ convert graph_test_cases.pdf graph_test_cases.jpg
convert-im6.q16: not authorized ‘graph_test_cases.pdf’ @ error/constitute.c/ReadImage/412.
convert-im6.q16: no images defined ‘graph_test_cases.jpg’ @ error/convert.c/ConvertImageCommand/3258.
        Command failure: error 1 !
$

$ identify -list policy | \grep -C4 PDF
    rights: None 
    pattern: EPS
  Policy: Coder
    rights: None 
    pattern: PDF
  Policy: Coder
    rights: None 
    pattern: XPS
$

  <policy domain="coder" rights="none" pattern="PDF" /> 

  <policy domain="coder" rights="read|write" pattern="PDF" />

$ identify -list policy | \grep -C4 PDF
    rights: None 
    pattern: EPS
  Policy: Coder
    rights: Read Write
    pattern: PDF
  Policy: Coder
    rights: None 
    pattern: XPS

$ convert -density 150 -quality 70 graph_test_cases.pdf graph_test_cases.jpg 
$ ll
total 6.5M
drwxrwxr-x 2 mse6s3 mse6s3 4.0K 2020-08-24 20:44 .
drwxrwxr-x 3 mse6s3 mse6s3  12K 2020-08-24 16:12 ..
-rw-rw-r-- 1 mse6s3 mse6s3 289K 2020-08-24 20:44 graph_test_cases-0.jpg
-rw-rw-r-- 1 mse6s3 mse6s3 235K 2020-08-24 20:44 graph_test_cases-1.jpg
-rw-rw-r-- 1 mse6s3 mse6s3 259K 2020-08-24 20:44 graph_test_cases-2.jpg
-rw-rw-r-- 1 mse6s3 mse6s3 240K 2020-08-24 20:44 graph_test_cases-3.jpg
-rw-rw-r-- 1 mse6s3 mse6s3 5.5M 2020-08-24 16:07 graph_test_cases.pdf

Konsole

• I have removed the shortcuts CTRL+PageUp and CTRL+PageDown in Konsole so as to be able to switch between VIM tabs. CTRL+SHIFT+← and CTRL+SHIFT+→ have been assigned to "move tab to the left" and "move tab to the right" in Settings → Configure Keyboard Shortcuts.
• here
• problem: the scrolling bar is hardly visible (black on black with only a tiny lighter border), and it is not possible to change that from the Konsole preferences:
  
  I am not the only one to complain about that: hereherehere. So it seems to be done on purpose! The last address suggest to change the colors of the terminal theme, and indeed it works. I have just chosen a lighter background in Konsole, instead of black:
  

Shutter not present from Ubuntu 18.04

$ sudo add-apt-repository -y ppa:linuxuprising/shutter
$ wajig install shutter

Crontab

$ crontab -l
# $PATH is empty when entering this script, so we are compelled to indicate all
# necessary directories in the hard-coded way. Note that /bin and /usr/bin are
# necessary for some of the programs used in bckup_exthd.sh below.
PATH=/usr/local/bin/:/bin:/usr/bin
SHELL=/bin/bash
# June 2017: DISPLAY=:0 is necessary for wmctrl to work below. Otherwise
# "cannot open display" error message is obtained.
DISPLAY=:0
# Random positioning of zenity windows for backup, and raise them on top of the window
# stack. Note how it is important to escape the "%" in the following line (see
# http://www.hcidata.info/crontab.htm). We do this every minute ("*/1") as the backup.
*/1 * * * *  unset w && for i in $(wmctrl -d|sed -n "s/.*\* DG: \([0-9]*\)x\([0-9]*\).*/\1 \2/p");do w[${#w[*]}]=$(( $RANDOM \% i ));done;wmctrl -R "pestering popup" -e 0,${w[0]},${w[1]},-1,-1;wmctrl -R "pestering popup"
*/1 * * * *  bckup_exthd.sh
*/7 * * * *  /usr/local/bin/leafnode_newmsg.sh

Automatic backup of user crontab

$ sudo ls -ld /var/spool/cron/crontabs/
drwx-wx--T 2 root crontab 4096 Oct 12 23:24 /var/spool/cron/crontabs/

$ \grep jscordi /etc/group
adm:x:4:syslog,jscordi
cdrom:x:24:jscordi
sudo:x:27:jscordi
dip:x:30:jscordi
plugdev:x:46:jscordi
crontab:x:105:jscordi
lpadmin:x:121:jscordi
lxd:x:131:jscordi
jscordi:x:1000:
sambashare:x:132:jscordi
$ groups
jscordi adm cdrom sudo dip plugdev crontab lpadmin lxd sambashare

$ sudo ls -ld /var/spool/cron/crontabs/jscordi
-rw------- 1 jscordi crontab 2855 Oct 12 23:24 /var/spool/cron/crontabs/jscordi

Philips 27’’ screen

$ xrandr --newmode "2560x1440_43.00"  217.50  2560 2720 2992 3424  1440 1443 1448 1478 -hsync +vsync
$ xrandr --addmode HDMI-1 "2560x1440_43.00"

Note about local package repository definition

$ cat /etc/apt/sources.list.d/local.list
deb [ allow-insecure=yes ] file:///usr/local/packages/installed /

$ sudo wajig update
Get:1 file:/usr/local/packages/installed  InRelease
Ign:1 file:/usr/local/packages/installed  InRelease
[…]
Get:9 file:/usr/local/packages/installed  Contents (deb)
Ign:9 file:/usr/local/packages/installed  Contents (deb)
Get:3 file:/usr/local/packages/installed  Packages [10.0 kB]
[…]
Reading package lists... Done                             
N: Download is performed unsandboxed as root as file ’/usr/local/packages/installed/InRelease’ couldn’t be accessed by user ’_apt’. - pkgAcquire::Run (13: Permission denied)
W: The repository ’file:/usr/local/packages/installed  Release’ does not have a Release file.
N: Data from such a repository can’t be authenticated and is therefore potentially dangerous to use.
N: See apt-secure(8) manpage for repository creation and user configuration details.
This is the same as the previous count with 0 new packages.
There are 0 new upgrades

$ cat /etc/apt/sources.list.d/local.list
deb [ trusted=yes ] file:///usr/local/packages/installed /

Fetched 107 kB in 1s (73.8 kB/s)    
Reading package lists... Done
N: Download is performed unsandboxed as root as file ’/usr/local/packages/installed/InRelease’ couldn’t be accessed by user ’_apt’. - pkgAcquire::Run (13: Permission denied)
This is the same as the previous count with 0 new packages.
There are 0 new upgrades

Scanner and Printer Canon MF4330d

$ ll /usr/local/packages/installed/cnrdrvcups-ufr2-uk_5.20-1_amd64.deb 
lrwxrwxrwx 1 jscordi jscordi 114 2020-10-12 23:50 /usr/local/packages/installed/cnrdrvcups-ufr2-uk_5.20-1_amd64.deb -> ../../non_src/CANON_MF4330d_v5_20/linux-UFRII-drv-v520-fr/64-bit_Driver/Debian/cnrdrvcups-ufr2-uk_5.20-1_amd64.deb

$ ./update_packages_gz.sh
$ wajig update

$ wajig install cnrdrvcups-ufr2-uk

 Canon MF4320-4350 (UFRII LT) CNUSBUFR2 #1 (Canon MF4320-4350 (UFRII LT))

thomas_precession_and_its_associated_grouplike_structure_AJP.pdf
whitrow_qjm_4_161_33.pdf

Syn60b.djvu

libdvdcss (DVD encryption) support

$ wajig install libdvd-pkg
$ sudo dpkg-reconfigure libdvd-pkg

Qarte

$ sudo apt-get install software-properties-common # for add-apt-repository
$ sudo add-apt-repository ppa:vincent-vandevyvre/vvv
$ apt install qarte

Pybliographer

$ wajig install pybliographer
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:
The following packages have unmet dependencies:
 pybliographer : Depends: python-gnome2 but it is not installable
                 Depends: python-glade2 but it is not installable
E: Unable to correct problems, you have held broken packages.

Pybliographer 1.4.0 is out. Changes include:
    Remove dependency on python-gnome2, python-gnome2-vfs, and python-glade2.
    Pybliographer now requires pygtk 2.24.0 and gettext 0.19.8
    Improve and simplify the build system
    Known regressions to be fixed later:
        Format entries cannot be saved 
    Known regressions that will not be fixed:
        Remove support for old confirmation dialog option
        Drop history on combo boxes

@incollection{MSM65,
	author = "Michel, Aim{\’e} and Stevens, William O. and Moufang, Wilhelm",
	booktitle = "{Encyclop{\’e}die Plan{\‘e}te"},
	title = "{Le myst{\‘e}re des r{\^e}ves"},
	year = 1965
}

:%s/"{\(.*\)"}/"\1"/g

$ wajig detail jabref
Package: jabref                   
Version: 3.8.2+ds-12
[…]

@Book{Sgu62,
  author    = {Saint-Guilhem, René},
  title     = {Les Principes de l’Analyse Dimensionnelle},
  publisher = {Gauthier-Villars},
  series    = {M\’emorial des sciences mathématiques},
  volume    = {152},
  booktitle = {Invariance des {R}elations {V}ectorielles dans {C}ertains {G}roupes d’{A}ffinit\’es},
  year      = {1962},
}

:%s/"\([^{].*[^}]\)"/{\1}/g
:%s/"\({.*}\)"/\1/g
:%s/"\(.*\)"/{\1}/g

	abstract = "p.103: remarque int{\’e}ressante sur la
                   probabilit{\’e} croissante avec le nombre de cas
                   apparent{\’e}s.",

$ echo -e ’= "Un Makefile ne\nsert pas seulement"’ | sed -z ’s+= "\([^"]*\)"+{\1}+’
{Un Makefile ne
sert pas seulement}

$ sed -z ’s+= "{\([^"]*\)}"+= {\1}+g’ biblio.bib > biblio2.bib
$ sed -z ’s+= "\([^{][^"]*\)"+= {\1}+g’ biblio2.bib > biblio3.bib

Plan{\‘e}te

Planète

\usepackage[utf8]{inputenc}

Turtlesport

$ turtlesport 
16:27:50,539 WARN  fr.turtlesport.TurtleSport - Turtle Sport v1.9
16:27:50,542 WARN  fr.turtlesport.TurtleSport - prop application.home=null
16:27:50,542 WARN  fr.turtlesport.TurtleSport - java.vendor=Ubuntu
16:27:50,543 WARN  fr.turtlesport.TurtleSport - java.runtime.name=OpenJDK Runtime Environment
16:27:50,544 WARN  fr.turtlesport.TurtleSport - java.version=11.0.8
16:27:50,544 WARN  fr.turtlesport.TurtleSport - java.vm.name=OpenJDK 64-Bit Server VM
16:27:50,545 WARN  fr.turtlesport.TurtleSport - java.vm.version=11.0.8+10-post-Ubuntu-0ubuntu120.04
16:27:50,546 WARN  fr.turtlesport.TurtleSport - sun.arch.data.model=64
16:27:50,546 WARN  fr.turtlesport.TurtleSport - prop application.home=null
16:27:50,547 WARN  fr.turtlesport.TurtleSport - os.name=Linux
16:27:50,547 WARN  fr.turtlesport.TurtleSport - os.arch=amd64
16:27:51,252 WARN  fr.turtlesport.db.DatabaseManager - derby.system.home=/home/jscordi/.turtlesport
16:27:51,254 WARN  fr.turtlesport.db.DatabaseManager - JDBC 4
16:27:51,544 WARN  fr.turtlesport.db.DatabaseManager - Using 10.3
16:27:52,050 WARN  fr.turtlesport.db.DatabaseManager - Using Apache Derby 10.3.1.4 - (561794)
could not load ’loading.png’
16:27:53,922 ERROR fr.turtlesport.map.MapConfiguration - 
java.lang.NoClassDefFoundError: javax/xml/bind/JAXBContext
        at fr.turtlesport.map.MapConfiguration.initMaps(MapConfiguration.java:96)
        at fr.turtlesport.map.MapConfiguration.<init>(MapConfiguration.java:55)
        at fr.turtlesport.map.MapConfiguration.<clinit>(MapConfiguration.java:37)
        at fr.turtlesport.map.AllMapsFactory.<init>(AllMapsFactory.java:74)
        at fr.turtlesport.map.AllMapsFactory.<clinit>(AllMapsFactory.java:26)
        at fr.turtlesport.ui.swing.component.JTurtleMapKit.getJComboboxMap(JTurtleMapKit.java:355)
        at fr.turtlesport.ui.swing.component.JTurtleMapKit.getJPanelButton(JTurtleMapKit.java:321)
        at fr.turtlesport.ui.swing.component.JTurtleMapKit.initialize(JTurtleMapKit.java:236)
        at fr.turtlesport.ui.swing.component.JTurtleMapKit.<init>(JTurtleMapKit.java:111)
        at fr.turtlesport.ui.swing.component.JPanelMap.getJMapKit(JPanelMap.java:101)
        at fr.turtlesport.ui.swing.component.JPanelMap.initialize(JPanelMap.java:84)
        at fr.turtlesport.ui.swing.component.JPanelMap.<init>(JPanelMap.java:35)
        at fr.turtlesport.ui.swing.JPanelRun.getJPanelMap(JPanelRun.java:1738)
        at fr.turtlesport.ui.swing.JPanelRun.getJSplitPanelCenter(JPanelRun.java:1684)
        at fr.turtlesport.ui.swing.JPanelRun.initialize(JPanelRun.java:556)
        at fr.turtlesport.ui.swing.JPanelRun.<init>(JPanelRun.java:281)
        at fr.turtlesport.ui.swing.MainGui.initialize(MainGui.java:604)
        at fr.turtlesport.ui.swing.MainGui.<init>(MainGui.java:205)
        at fr.turtlesport.ui.swing.SwingApplication.createMainGUI(SwingApplication.java:235)
        at fr.turtlesport.ui.swing.SwingApplication.access$000(SwingApplication.java:34)
        at fr.turtlesport.ui.swing.SwingApplication$2.run(SwingApplication.java:154)
        at java.desktop/java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:313)
        at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:770)
        at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:721)
        at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:715)
        at java.base/java.security.AccessController.doPrivileged(Native Method)
        at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85)
        at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:740)
        at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)
        at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)
        at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113)
        at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109)
        at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
        at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90)
Caused by: java.lang.ClassNotFoundException: javax.xml.bind.JAXBContext
        at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:581)
        at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
        at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522)
        ... 34 more
Exception in thread "AWT-EventQueue-0" java.lang.NoClassDefFoundError: javax/activation/ActivationDataFlavor
        at fr.turtlesport.ui.swing.component.calendar.JLabelDay.fireActive(JLabelDay.java:152)
        at fr.turtlesport.ui.swing.component.calendar.AbstractJPanelMonth.fireCurrentDates(AbstractJPanelMonth.java:226)
        at fr.turtlesport.ui.swing.model.ModelRunCalendar.updateView(ModelRunCalendar.java:74)
        at fr.turtlesport.ui.swing.component.calendar.JPanelCalendar.fireHistoric(JPanelCalendar.java:149)
        at fr.turtlesport.ui.swing.component.calendar.JPanelListDateRun.fireHistoric(JPanelListDateRun.java:188)
        at fr.turtlesport.ui.swing.MainGui.fireHistoric(MainGui.java:1560)
        at fr.turtlesport.ui.swing.MainGui.setCurrentIdUser(MainGui.java:367)
        at fr.turtlesport.ui.swing.MainGui.initialize(MainGui.java:605)
        at fr.turtlesport.ui.swing.MainGui.<init>(MainGui.java:205)
        at fr.turtlesport.ui.swing.SwingApplication.createMainGUI(SwingApplication.java:235)
        at fr.turtlesport.ui.swing.SwingApplication.access$000(SwingApplication.java:34)
        at fr.turtlesport.ui.swing.SwingApplication$2.run(SwingApplication.java:154)
        at java.desktop/java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:313)
        at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:770)
        at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:721)
        at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:715)
        at java.base/java.security.AccessController.doPrivileged(Native Method)
        at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85)
        at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:740)
        at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)
        at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)
        at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113)
        at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109)
        at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
        at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90)
Caused by: java.lang.ClassNotFoundException: javax.activation.ActivationDataFlavor
        at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:581)
        at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
        at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522)

Ton erreur est indiquée par ces messages :
java.lang.NoClassDefFoundError: javax/xml/bind/JAXBContext
java.lang.ClassNotFoundException: javax.activation.ActivationDataFlavor
Tu utilises Java en version 10.
Ton problème vient de ce que, une des classes utilisées par Turtle Sport 2.0-1, est dépréciée depuis Java 9.
Pour corriger ton problème, il faut installer le paquet openjdk-8-jre. Ensuite, il te faut, soit mettre cette version par défaut, soit préciser la version à utiliser en lançant Turtle Sport.

$ wajig install openjdk-8-jre
$ sudo update-alternatives --config java
There are 2 choices for the alternative java (providing /usr/bin/java).
  Selection    Path                                            Priority   Status
------------------------------------------------------------
* 0            /usr/lib/jvm/java-11-openjdk-amd64/bin/java      1111      auto mode
  1            /usr/lib/jvm/java-11-openjdk-amd64/bin/java      1111      manual mode
  2            /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java   1081      manual mode
Press <enter> to keep the current choice[*], or type selection number: 2
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java to provide /usr/bin/java (java) in manual mode

En bref, la machine virtuelle Java ou JVM est le composant de la plate-forme Java qui exécute les programmes ; l’environnement de développement Java ou JRE crée la machine virtuelle Java ou JVM et s’assure que les dépendances sont disponibles pour les programmes Java ; le kit de développement Java ou JDK permet de créer des programmes Java qui peuvent être exécutés par la JVM et le JRE.

gcolor2 is missing

Various

• the configuration of the compose key done in previous installations still works.

Connecting my Garmin watch at startup at best slows down the boot a lot

dmesg.0-        [   25.172173] kernel: ACPI: \_SB_.PCI0.PEG0.PEGP: failed to evaluate _DSM
dmesg.0-        [   36.296038] kernel: usb 3-3.4: reset full-speed USB device number 6 using xhci_hcd
dmesg.0-        [   36.421569] kernel: sd 4:0:0:0: Power-on or device reset occurred
dmesg.0-        [   51.656066] kernel: usb 3-3.4: reset full-speed USB device number 6 using xhci_hcd
dmesg.0-        [   51.987715] kernel: EXT4-fs (sda1): mounted filesystem with ordered data mode. Opts: (null)
dmesg.0-        [   51.987725] kernel: ext4 filesystem being mounted at /boot supports timestamps until 2038 (0x7fffffff)
dmesg.0-        [   67.016098] kernel: usb 3-3.4: reset full-speed USB device number 6 using xhci_hcd
dmesg.0-        [   97.480097] kernel: usb 3-3.4: reset full-speed USB device number 6 using xhci_hcd
dmesg.0-        [   97.604989] kernel: sd 4:0:0:0: [sdc] tag#0 FAILED Result: hostbyte=DID_TIME_OUT driverbyte=DRIVER_OK
dmesg.0-        [   97.604994] kernel: sd 4:0:0:0: [sdc] tag#0 CDB: Read(10) 28 00 00 00 20 00 00 00 08 00
dmesg.0:        [   97.604997] kernel: blk_update_request: I/O error, dev sdc, sector 8192 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0
dmesg.0-        [   97.606023] kernel: sd 4:0:0:0: Power-on or device reset occurred

Prevent Ubuntu from updating the kernel over and over

$ sudo apt-mark hold linux-image-generic linux-headers-generic
linux-image-generic was already set on hold.
linux-headers-generic set on hold.

$ cd /boot
$ rm -f initrd.img*

$ wajig install dolphin
$ ls -l initrd.img*
lrwxrwxrwx 1 root root       27 déc.   6 11:38 initrd.img -> initrd.img-5.4.0-56-generic
-rw-r--r-- 1 root root 87095527 déc.   6 11:39 initrd.img-5.4.0-56-generic

$ sudo apt-mark hold 5.4.0-56-generic
linux-buildinfo-5.4.0-56-generic set on hold.
linux-cloud-tools-5.4.0-56-generic set on hold.
linux-headers-5.4.0-56-generic set on hold.
linux-image-5.4.0-56-generic set on hold.
linux-modules-5.4.0-56-generic set on hold.
linux-image-unsigned-5.4.0-56-generic set on hold.
linux-modules-extra-5.4.0-56-generic set on hold.
linux-tools-5.4.0-56-generic set on hold.
linux-modules-nvidia-390-5.4.0-56-generic set on hold.
linux-modules-nvidia-418-server-5.4.0-56-generic set on hold.
linux-modules-nvidia-440-server-5.4.0-56-generic set on hold.
linux-modules-nvidia-450-5.4.0-56-generic set on hold.
linux-modules-nvidia-450-server-5.4.0-56-generic set on hold.
linux-modules-nvidia-455-5.4.0-56-generic set on hold.
$

Update on December 13: Realtek hardware (network card and card reader) no more listed

$ lspci|grep realtek
        Command failure: error 1 !

$ uname -r
5.4.0-56-generic

$ cd /boot
$ rm -f initrd.img*
$ update-initramfs -k all -c -v
$ ls /boot
grub        System.map-5.4.0-53-generic  System.map-5.6.0-1028-oem    config-5.4.0-53-generic  config-5.6.0-1028-oem    initrd.img-5.4.0-56-generic  memtest86+.elf            vmlinuz
lost+found  System.map-5.4.0-56-generic  System.map-5.8.0-29-generic  config-5.4.0-56-generic  config-5.8.0-29-generic  memtest86+.bin               memtest86+_multiboot.bin  vmlinuz-5.4.0-56-generic
$ ll /boot/vmlinuz
lrwxrwxrwx 1 root root 24 2020-12-13 11:35 /boot/vmlinuz -> vmlinuz-5.4.0-56-generic
$ update-grub
$

$ uname -r
5.4.0-56-generic
$ lspci|grep realt
04:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTL8411 PCI Express Card Reader (rev 01)
04:00.2 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 0a)

Update on June 3, 2021: hibernation

$ sudo journalctl | grep -C100 systemd-sleep
[…]
Sep 26 17:53:28 rama systemd-sleep[30695]: Suspending system...
Sep 26 17:53:28 rama kernel: PM: Syncing filesystems ... done.
Sep 26 17:53:28 rama kernel: PM: Preparing system for sleep (mem)
Sep 26 17:55:56 rama kernel: (NULL device *): firmware: direct-loading firmware iwlwifi-2030-6.ucode
Sep 26 17:55:56 rama kernel: Freezing user space processes ... (elapsed 0.001 seconds) done.
Sep 26 17:55:56 rama kernel: Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
Sep 26 17:55:56 rama kernel: PM: Suspending system (mem)
Sep 26 17:55:56 rama kernel: Suspending console(s) (use no_console_suspend to debug)
Sep 26 17:55:56 rama kernel: sd 1:0:0:0: [sdb] Synchronizing SCSI cache
Sep 26 17:55:56 rama kernel: sd 0:0:0:0: [sda] Synchronizing SCSI cache
Sep 26 17:55:56 rama kernel: sd 0:0:0:0: [sda] Stopping disk
Sep 26 17:55:56 rama kernel: sd 1:0:0:0: [sdb] Stopping disk
Sep 26 17:55:56 rama kernel: nouveau 0000:01:00.0: DRM: resuming kernel object tree...
Sep 26 17:55:56 rama kernel: nouveau 0000:01:00.0: DRM: resuming client object trees...
Sep 26 17:55:56 rama kernel: nouveau 0000:01:00.0: DRM: evicting buffers...
Sep 26 17:55:56 rama kernel: nouveau 0000:01:00.0: DRM: waiting for kernel channels to go idle...
Sep 26 17:55:56 rama kernel: nouveau 0000:01:00.0: DRM: suspending client object trees...
Sep 26 17:55:56 rama kernel: nouveau 0000:01:00.0: DRM: suspending kernel object tree...
Sep 26 17:55:56 rama kernel: PM: suspend of devices complete after 3536.794 msecs
Sep 26 17:55:56 rama kernel: PM: late suspend of devices complete after 19.707 msecs
Sep 26 17:55:56 rama kernel: pcieport 0000:00:1c.3: System wakeup enabled by ACPI
Sep 26 17:55:56 rama kernel: ehci-pci 0000:00:1d.0: System wakeup enabled by ACPI
Sep 26 17:55:56 rama kernel: ehci-pci 0000:00:1a.0: System wakeup enabled by ACPI
Sep 26 17:55:56 rama kernel: xhci_hcd 0000:00:14.0: System wakeup enabled by ACPI
Sep 26 17:55:56 rama kernel: PM: noirq suspend of devices complete after 20.035 msecs
Sep 26 17:55:56 rama kernel: ACPI: Preparing to enter system sleep state S3
Sep 26 17:55:56 rama kernel: ACPI : EC: event blocked
Sep 26 17:55:56 rama kernel: ACPI : EC: EC stopped
Sep 26 17:55:56 rama kernel: PM: Saving platform NVS memory
Sep 26 17:55:56 rama kernel: Disabling non-boot CPUs ...
Sep 26 17:55:56 rama kernel: Broke affinity for irq 31
Sep 26 17:55:56 rama kernel: smpboot: CPU 1 is now offline
Sep 26 17:55:56 rama kernel: Broke affinity for irq 16
Sep 26 17:55:56 rama kernel: Broke affinity for irq 27
Sep 26 17:55:56 rama kernel: Broke affinity for irq 28
Sep 26 17:55:56 rama kernel: Broke affinity for irq 31
Sep 26 17:55:56 rama kernel: Broke affinity for irq 33
Sep 26 17:55:56 rama kernel: smpboot: CPU 2 is now offline
Sep 26 17:55:56 rama kernel: Broke affinity for irq 1
Sep 26 17:55:56 rama kernel: Broke affinity for irq 9
Sep 26 17:55:56 rama kernel: Broke affinity for irq 12
Sep 26 17:55:56 rama kernel: Broke affinity for irq 16
Sep 26 17:55:56 rama kernel: Broke affinity for irq 23
Sep 26 17:55:56 rama kernel: Broke affinity for irq 26
Sep 26 17:55:56 rama kernel: Broke affinity for irq 27
Sep 26 17:55:56 rama kernel: Broke affinity for irq 28
Sep 26 17:55:56 rama kernel: Broke affinity for irq 31
Sep 26 17:55:56 rama kernel: Broke affinity for irq 33
Sep 26 17:55:56 rama kernel: smpboot: CPU 3 is now offline
Sep 26 17:55:56 rama kernel: ACPI: Low-level resume complete
[…]

$ top
[…]
%Cpu(s):  4.1 us, 20.5 sy,  2.7 ni, 35.6 id, 35.6 wa,  0.0 hi,  1.4 si,  0.0 st
MiB Mem :   7858.2 total,    439.4 free,   2198.0 used,   5220.8 buff/cache
MiB Swap:   9536.0 total,   9487.0 free,     49.0 used.   4862.1 avail Mem

$ sudo lsblk 
NAME                  MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINT
loop0                   7:0    0  55.5M  1 loop  /snap/core18/1997
loop1                   7:1    0 138.9M  1 loop  /snap/chromium/1589
loop2                   7:2    0  55.4M  1 loop  /snap/core18/2066
loop3                   7:3    0  64.8M  1 loop  /snap/gtk-common-themes/1514
loop4                   7:4    0 141.4M  1 loop  /snap/chromium/1608
loop5                   7:5    0 162.9M  1 loop  /snap/gnome-3-28-1804/145
loop6                   7:6    0  32.1M  1 loop  /snap/snapd/11841
loop7                   7:7    0  65.1M  1 loop  /snap/gtk-common-themes/1515
loop8                   7:8    0  32.1M  1 loop  /snap/snapd/12057
sda                     8:0    0  83.9G  0 disk  
├─sda1                  8:1    0   190M  0 part  /boot
├─sda2                  8:2    0     1K  0 part  
└─sda5                  8:5    0  83.7G  0 part  
  └─sda5_crypt        253:0    0  83.7G  0 crypt 
    ├─vg-lv_swap      253:1    0   9.3G  0 lvm   [SWAP]
    ├─vg-lv_root      253:2    0  30.5G  0 lvm   /
    ├─vg-vg_usrlocal  253:3    0    28G  0 lvm   /usr/local
    └─vg-lv_homelocal 253:4    0  15.9G  0 lvm   /home/local
sdb                     8:16   0   1.8T  0 disk  
└─sdb1                  8:17   0   1.8T  0 part  
  └─sdb1_crypt        253:5    0   1.8T  0 crypt /home
sr0                    11:0    1  1024M  0 rom   
$ sudo lvs
  WARNING: PV /dev/mapper/sda5_crypt in VG vg is using an old PV header, modify the VG to update.
  LV           VG Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  lv_homelocal vg -wi-ao----  15.91g                                                    
  lv_root      vg -wi-ao----  30.49g                                                    
  lv_swap      vg -wi-ao----   9.31g                                                    
  vg_usrlocal  vg -wi-ao---- <27.94g                                                    

$ swapoff -a
$ lvextend -L +2G /dev/mapper/vg-lv_swap
[…]
$ mkswap /dev/mapper/vg-lv_swap
[…]
$ swapon -a

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash resume=/dev/dm-1"

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash resume=/dev/mapper/vg-lv_swap"

• buy a large evolutive tower PC where I will be able to replace damaged components in the future; I will not anymore take the risk of buying a laptop that may last only two years as it happened to me in 2010;
• when in displacement (vacation), use my old laptop as 20 years ago: boot and shutdown every day. The files on which I work will be on an encrypted USB key and transfered back to the main tower PC using a dedicated UNISON command line. I never saw my laptop stop itself alone once booted, the problems only happen during suspend or hibernation; thus used like that it should be able to last several more years.