J'ai eu la flemme de réinstaller. J'ai fini par explorer un peu les logs :
mai 20 21:36:05 zefling-1 udisksd[775]: Failed to load the 'mdraid' libblockdev plugin
mai 20 21:36:06 zefling-1 sddm[895]: Session "plasma.desktop" selected, command: "/usr/bin/startkde"
mai 20 21:36:06 zefling-1 sddm-helper[1077]: Starting: "/etc/sddm/Xsession \"/usr/bin/startkde\""
mai 20 21:36:07 zefling-1 dbus-daemon[1134]: [session uid=1000 pid=1134] Activating service name='org.kde.ActivityManager' requested by ':1.23' (uid=1000 pid=1328 comm="kded5 [kdeinit5] " label="unconfined")
mai 20 21:36:07 zefling-1 dbus-daemon[1134]: [session uid=1000 pid=1134] Successfully activated service 'org.kde.ActivityManager'
mai 20 21:36:07 zefling-1 org.kde.ActivityManager[1134]: Config timer connecting...
mai 20 21:36:07 zefling-1 org.kde.ActivityManager[1134]: Setting the name of 0x55d3cc704600 to "org.kde.ActivityManager.ActivityTemplates"
mai 20 21:36:07 zefling-1 org.kde.ActivityManager[1134]: Setting the name of 0x55d3cc70e0e0 to "org.kde.ActivityManager.RunApplication"
mai 20 21:36:07 zefling-1 org.kde.ActivityManager[1134]: Setting the name of 0x55d3cc70ce60 to "org.kde.ActivityManager.Resources.Scoring"
mai 20 21:36:07 zefling-1 org.kde.ActivityManager[1134]: Creating directory: "/home/zefling/.local/share/kactivitymanagerd/resources/"
mai 20 21:36:07 zefling-1 org.kde.ActivityManager[1134]: KActivities: Database connection: "kactivities_db_resources_140020395740288_readwrite"
mai 20 21:36:07 zefling-1 org.kde.ActivityManager[1134]: query_only: QVariant(qlonglong, 0)
mai 20 21:36:07 zefling-1 org.kde.ActivityManager[1134]: journal_mode: QVariant(QString, "wal")
mai 20 21:36:07 zefling-1 org.kde.ActivityManager[1134]: wal_autocheckpoint: QVariant(qlonglong, 100)
mai 20 21:36:07 zefling-1 org.kde.ActivityManager[1134]: synchronous: QVariant(qlonglong, 1)
mai 20 21:36:07 zefling-1 org.kde.ActivityManager[1134]: Service started, version: 7.0.0
mai 20 21:36:07 zefling-1 org.kde.ActivityManager[1134]: Cleaning up...
mai 20 21:36:07 zefling-1 dbus-daemon[1134]: [session uid=1000 pid=1134] Activating service name='org.kde.kglobalaccel' requested by ':1.23' (uid=1000 pid=1328 comm="kded5 [kdeinit5] " label="unconfined")
mai 20 21:36:07 zefling-1 dbus-daemon[1134]: [session uid=1000 pid=1134] Successfully activated service 'org.kde.kglobalaccel'
mai 20 21:36:07 zefling-1 dbus-daemon[752]: [system] Activating via systemd: service name='org.freedesktop.UPower' unit='upower.service' requested by ':1.31' (uid=1000 pid=1328 comm="kded5 [kdeinit5] " label="unconfined")
mai 20 21:36:08 zefling-1 polkitd(authority=local)[812]: Registered Authentication Agent for unix-session:1 (system bus name :1.37 [/usr/lib/x86_64-linux-gnu/libexec/polkit-kde-authentication-agent-1], object path /org/kde/PolicyKit1/AuthenticationAgent, locale fr_FR.UTF-8)
mai 20 21:36:08 zefling-1 dbus-daemon[1134]: [session uid=1000 pid=1134] Activating service name='org.kde.KScreen' requested by ':1.23' (uid=1000 pid=1328 comm="kded5 [kdeinit5] " label="unconfined")
mai 20 21:36:08 zefling-1 dbus-daemon[1134]: [session uid=1000 pid=1134] Successfully activated service 'org.kde.KScreen'
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Connected output 102 to CRTC 95
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Detected XRandR 1.5
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Event Base: 89
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Event Error: 147
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: XRandR::setConfig
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Requested screen size is QSize(3840, 2160)
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Needed CRTCs: 1
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Actions to perform:
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Primary Output: true
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Old: 99
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: New: 102
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Change Screen Size: false
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Disable outputs: false
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Change outputs: false
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Enable outputs: false
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: RRSetOutputPrimary
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: New primary: 102
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: XRandR::setConfig done!
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: RRNotify_OutputChange
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Output: 99
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: CRTC: 0
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Mode: 0
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Rotation: "Rotate_0"
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Connection: "Disconnected"
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Subpixel Order: 0
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: RRNotify_OutputChange
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Output: 102
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: CRTC: 95
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Mode: 104
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Rotation: "Rotate_0"
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Connection: "Connected"
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Subpixel Order: 0
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: RRScreenChangeNotify
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Window: 48234500
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Root: 1279
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Rotation: "Rotate_0"
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Size ID: 0
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Size: 3840 2160
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: SizeMM: 1016 571
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: RRNotify_OutputChange
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Output: 99
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: CRTC: 0
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Mode: 0
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Rotation: "Rotate_0"
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Connection: "Disconnected"
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Subpixel Order: 0
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: RRNotify_OutputChange
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Output: 102
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: CRTC: 95
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Mode: 104
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Rotation: "Rotate_0"
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Connection: "Connected"
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xcb.helper: Subpixel Order: 0
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: XRandROutput 99 update
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: m_connected: 1
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: m_crtc QObject(0x0)
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: CRTC: 0
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: MODE: 0
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Connection: 1
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Primary: false
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Output 99 : connected = false , enabled = false
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: XRandROutput 102 update
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: m_connected: 0
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: m_crtc XRandRCrtc(0x556a9ddf9ed0)
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: CRTC: 95
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: MODE: 104
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Connection: 0
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Primary: true
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Output 102 : connected = true , enabled = true
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: XRandROutput 99 update
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: m_connected: 1
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: m_crtc QObject(0x0)
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: CRTC: 0
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: MODE: 0
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Connection: 1
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Primary: false
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Output 99 : connected = false , enabled = false
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: XRandROutput 102 update
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: m_connected: 0
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: m_crtc XRandRCrtc(0x556a9ddf9ed0)
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: CRTC: 95
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: MODE: 104
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Connection: 0
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Primary: true
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Output 102 : connected = true , enabled = true
mai 20 21:36:08 zefling-1 dbus-daemon[752]: [system] Activating service name='org.kde.powerdevil.discretegpuhelper' requested by ':1.40' (uid=1000 pid=1442 comm="/usr/lib/x86_64-linux-gnu/libexec/org_kde_powerdev" label="unconfined") (using servicehelper)
mai 20 21:36:08 zefling-1 org.kde.powerdevil.discretegpuhelper[1495]: QDBusArgument: read from a write-only object
mai 20 21:36:08 zefling-1 org.kde.powerdevil.discretegpuhelper[1495]: QDBusArgument: read from a write-only object
mai 20 21:36:08 zefling-1 org.kde.powerdevil.discretegpuhelper[1495]: QDBusArgument: read from a write-only object
mai 20 21:36:08 zefling-1 dbus-daemon[752]: [system] Successfully activated service 'org.kde.powerdevil.discretegpuhelper'
mai 20 21:36:08 zefling-1 dbus-daemon[752]: [system] Activating service name='org.kde.powerdevil.backlighthelper' requested by ':1.40' (uid=1000 pid=1442 comm="/usr/lib/x86_64-linux-gnu/libexec/org_kde_powerdev" label="unconfined") (using servicehelper)
mai 20 21:36:08 zefling-1 org.kde.powerdevil.backlighthelper[752]: powerdevil: no kernel backlight interface found
mai 20 21:36:08 zefling-1 org.kde.powerdevil.backlighthelper[1501]: QDBusArgument: read from a write-only object
mai 20 21:36:08 zefling-1 org.kde.powerdevil.backlighthelper[1501]: QDBusArgument: read from a write-only object
mai 20 21:36:08 zefling-1 org.kde.powerdevil.backlighthelper[1501]: QDBusArgument: read from a write-only object
mai 20 21:36:08 zefling-1 dbus-daemon[752]: [system] Successfully activated service 'org.kde.powerdevil.backlighthelper'
mai 20 21:36:08 zefling-1 org.kde.KScreen[1134]: kscreen.xrandr: Emitting configChanged()
mai 20 21:36:09 zefling-1 dbus-daemon[752]: [system] Activating via systemd: service name='org.bluez' unit='dbus-org.bluez.service' requested by ':1.31' (uid=1000 pid=1328 comm="kded5 [kdeinit5] " label="unconfined")
mai 20 21:36:09 zefling-1 dbus-daemon[1134]: [session uid=1000 pid=1134] Activating via systemd: service name='org.bluez.obex' unit='dbus-org.bluez.obex.service' requested by ':1.23' (uid=1000 pid=1328 comm="kded5 [kdeinit5] " label="unconfined")
mai 20 21:36:11 zefling-1 dbus-daemon[1134]: [session uid=1000 pid=1134] Activating service name='org.kde.kuiserver' requested by ':1.35' (uid=1000 pid=1390 comm="/usr/bin/plasmashell " label="unconfined")
mai 20 21:36:11 zefling-1 org.kde.kuiserver[1134]: QDBusConnection: session D-Bus connection created before QCoreApplication. Application may misbehave.
mai 20 21:36:11 zefling-1 dbus-daemon[1134]: [session uid=1000 pid=1134] Successfully activated service 'org.kde.kuiserver'
mai 20 21:36:11 zefling-1 org.kde.kuiserver[1134]: QDBusConnection: session D-Bus connection created before QCoreApplication. Application may misbehave.
Bizarrement à commence toujours par « Failed to load the 'mdraid' libblockdev plugin ».
Je vais essayer un ça, mais comme c'est complètement aléatoire, je vais devoir attendre pour voir si ça marche :
aptitude install libblockdev-mdraid2
Édit : Ça pourrait plutôt venir de ça :
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=864349