I managed to acquire a journalctl -xe after reboot.
I removed a few entries related to modem manager etc. There are a few errors related to kde. In this case, i rebooted into a gray screen with a mouse cursor movable but nothing else could be done.
@bogdancovaciu
Attempting to run kwin_x11 --replace & or plasmashell --replace & gives 100s of errors in tty.
okt 13 18:32:29 albert-ms7c04 org_kde_powerdevil[1375]: powerdevil: Current session is now active
okt 13 18:32:29 albert-ms7c04 org_kde_powerdevil[1375]: powerdevil: ACTIVE SESSION PATH CHANGED: "/org/freedesktop/login1/session/_32"
okt 13 18:32:29 albert-ms7c04 org_kde_powerdevil[1375]: powerdevil: Current session is now active
okt 13 18:32:29 albert-ms7c04 plasmashell[1161]: qrc:/plasma/plasmoids/org.kde.plasma.volume/contents/ui/main.qml:550:39: QML DeviceListItem: Binding loop detected for property "width"
okt 13 18:32:29 albert-ms7c04 kded5[1107]: bluedevil: About to resume
okt 13 18:32:29 albert-ms7c04 plasmashell[1161]: file:///usr/lib/qt/qml/QtQuick/Controls/Styles/Plasma/ToolButtonStyle.qml:196:13: QML Connections: Implicitly defined onFoo properties in Connections are deprecated. Use this syntax instead: function onFoo(<arguments>) { ... }
okt 13 18:32:29 albert-ms7c04 plasmashell[1161]: file:///usr/lib/qt/qml/QtQuick/Controls/Styles/Plasma/ToolButtonStyle.qml:196:13: QML Connections: Implicitly defined onFoo properties in Connections are deprecated. Use this syntax instead: function onFoo(<arguments>) { ... }
okt 13 18:32:29 albert-ms7c04 kcminit[15384]: Initializing "kcm_mouse" : "kcminit_mouse"
okt 13 18:32:29 albert-ms7c04 kwin_x11[1111]: qt.qpa.xcb: QXcbConnection: XCB error: 3 (BadWindow), sequence: 19410, resource id: 134217733, major code: 18 (ChangeProperty), minor code: 0
okt 13 18:32:30 albert-ms7c04 kcminit[15398]: Initializing "kcm_mouse" : "kcminit_mouse"
okt 13 18:32:30 albert-ms7c04 kwin_x11[1111]: qt.qpa.xcb: QXcbConnection: XCB error: 3 (BadWindow), sequence: 21341, resource id: 136314885, major code: 18 (ChangeProperty), minor code: 0
okt 13 18:32:30 albert-ms7c04 kcminit[15409]: Initializing "kcm_mouse" : "kcminit_mouse"
okt 13 18:32:30 albert-ms7c04 kwin_x11[1111]: qt.qpa.xcb: QXcbConnection: XCB error: 3 (BadWindow), sequence: 22324, resource id: 136314885, major code: 18 (ChangeProperty), minor code: 0
okt 13 18:32:31 albert-ms7c04 ModemManager[491]: <info> [base-manager] couldn't check support for device '/sys/devices/pci0000:00/0000:00:14.3': not supported by any plugin
okt 13 18:32:31 albert-ms7c04 ModemManager[491]: <info> [base-manager] couldn't check support for device '/sys/devices/pci0000:00/0000:00:1c.4/0000:03:00.0': not supported by any plugin
okt 13 18:32:32 albert-ms7c04 kernel: r8169 0000:03:00.0 enp3s0: Link is Up - 1Gbps/Full - flow control rx/tx
okt 13 18:32:32 albert-ms7c04 kernel: IPv6: ADDRCONF(NETDEV_CHANGE): enp3s0: link becomes ready
okt 13 18:32:32 albert-ms7c04 avahi-daemon[442]: Joining mDNS multicast group on interface enp3s0.IPv6 with address fe80::d939:88cf:1508:3b02.
okt 13 18:32:32 albert-ms7c04 avahi-daemon[442]: New relevant interface enp3s0.IPv6 for mDNS.
okt 13 18:32:32 albert-ms7c04 avahi-daemon[442]: Registering new address record for fe80::d939:88cf:1508:3b02 on enp3s0.*.
okt 13 18:32:32 albert-ms7c04 kded5[1107]: plasma-nm: Unhandled active connection state change: 1
okt 13 18:32:33 albert-ms7c04 kernel: ata4: link is slow to respond, please be patient (ready=0)
okt 13 18:32:34 albert-ms7c04 avahi-daemon[442]: Joining mDNS multicast group on interface enp3s0.IPv4 with address 192.168.0.111.
okt 13 18:32:34 albert-ms7c04 NetworkManager[446]: <info> [1602606754.1004] dhcp4 (enp3s0): option requested_rfc3442_classless_static_routes => '1'
okt 13 18:32:34 albert-ms7c04 avahi-daemon[442]: New relevant interface enp3s0.IPv4 for mDNS.
okt 13 18:32:34 albert-ms7c04 NetworkManager[446]: <info> [1602606754.1004] dhcp4 (enp3s0): option requested_root_path => '1'
okt 13 18:32:34 albert-ms7c04 avahi-daemon[442]: Registering new address record for 192.168.0.111 on enp3s0.IPv4.
okt 13 18:32:34 albert-ms7c04 kded5[1107]: plasma-nm: Not emitting connection activated notification as the connection was active prior to suspend
okt 13 18:32:34 albert-ms7c04 NetworkManager[446]: <info> [1602606754.1939] manager: NetworkManager state is now CONNECTED_GLOBAL
okt 13 18:32:35 albert-ms7c04 kernel: kauditd_printk_skb: 77 callbacks suppressed
okt 13 18:32:35 albert-ms7c04 kernel: audit: type=1131 audit(1602606755.536:116): pid=1 uid=0 auid=4294967295 ses=4294967295 subj==unconfined msg='unit=NetworkManager-dispatcher comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
okt 13 18:32:35 albert-ms7c04 audit[1]: SERVICE_STOP pid=1 uid=0 auid=4294967295 ses=4294967295 subj==unconfined msg='unit=NetworkManager-dispatcher comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
okt 13 18:32:35 albert-ms7c04 systemd[1]: NetworkManager-dispatcher.service: Succeeded.
░░ Subject: Unit succeeded
░░ Defined-By: systemd
░░ Support: https://forum.manjaro.org/c/support
░░
░░ The unit NetworkManager-dispatcher.service has successfully entered the 'dead' state.
okt 13 18:32:36 albert-ms7c04 kernel: snd_hda_intel 0000:01:00.1: spurious response 0x80000000:0x0, last cmd=0x4f0900
okt 13 18:32:36 albert-ms7c04 kernel: snd_hda_intel 0000:01:00.1: spurious response 0x0:0x0, last cmd=0x4f0900
okt 13 18:32:36 albert-ms7c04 kernel: snd_hda_intel 0000:01:00.1: spurious response 0xc0000000:0x0, last cmd=0x4f0015
okt 13 18:32:36 albert-ms7c04 kernel: snd_hda_intel 0000:01:00.1: spurious response 0x3:0x0, last cmd=0x473500
okt 13 18:32:36 albert-ms7c04 systemd[1]: Started Getty on tty2.
░░ Subject: A start job for unit getty@tty2.service has finished successfully
░░ Defined-By: systemd
░░ Support: https://forum.manjaro.org/c/support
░░
░░ A start job for unit getty@tty2.service has finished successfully.
░░
░░ The job identifier is 1777.
okt 13 18:32:36 albert-ms7c04 audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 subj==unconfined msg='unit=getty@tty2 comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
okt 13 18:32:36 albert-ms7c04 kernel: audit: type=1130 audit(1602606756.953:117): pid=1 uid=0 auid=4294967295 ses=4294967295 subj==unconfined msg='unit=getty@tty2 comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
okt 13 18:32:36 albert-ms7c04 kernel: fbcon: Taking over console
okt 13 18:32:36 albert-ms7c04 kernel: Console: switching to colour frame buffer device 160x45
okt 13 18:32:37 albert-ms7c04 org_kde_powerdevil[1375]: powerdevil: ACTIVE SESSION PATH CHANGED: "/"
okt 13 18:32:37 albert-ms7c04 org_kde_powerdevil[1375]: powerdevil: Switched to inactive session - leaving unchanged
okt 13 18:32:37 albert-ms7c04 plasmashell[1161]: QOpenGLFramebufferObject: Unsupported framebuffer format.
okt 13 18:32:37 albert-ms7c04 plasmashell[1161]: QOpenGLFramebufferObject: Framebuffer incomplete, missing attachment.
okt 13 18:32:37 albert-ms7c04 plasmashell[1161]: QOpenGLFramebufferObject: Unsupported framebuffer format.
okt 13 18:32:37 albert-ms7c04 plasmashell[1161]: QOpenGLFramebufferObject: Framebuffer incomplete, missing attachment.
okt 13 18:32:37 albert-ms7c04 plasmashell[1161]: QOpenGLFramebufferObject: Unsupported framebuffer format.
okt 13 18:32:37 albert-ms7c04 plasmashell[1161]: QOpenGLFramebufferObject: Framebuffer incomplete, missing attachment.
okt 13 18:32:37 albert-ms7c04 plasmashell[1161]: QOpenGLFramebufferObject: Unsupported framebuffer format.
okt 13 18:32:37 albert-ms7c04 plasmashell[1161]: QOpenGLFramebufferObject: Framebuffer incomplete, missing attachment.
okt 13 18:32:37 albert-ms7c04 plasmashell[1161]: qrc:/plasma/plasmoids/org.kde.plasma.volume/contents/ui/main.qml:550:39: QML DeviceListItem: Binding loop detected for property "width"
okt 13 18:32:37 albert-ms7c04 baloo_file[1168]: 35500584761099010 "/home/abbe/Dev/GregTech/run/logs/latest.log" renaming "debug-1.log" to "latest.log"
okt 13 18:32:37 albert-ms7c04 baloo_file[1168]: 35540132819960578 "/home/abbe/Dev/GregTech/run/logs/debug.log" renaming "debug-5.log.gz" to "debug.log"
okt 13 18:32:37 albert-ms7c04 rtkit-daemon[1247]: Supervising 7 threads of 2 processes of 1 users.
okt 13 18:32:37 albert-ms7c04 rtkit-daemon[1247]: Supervising 7 threads of 2 processes of 1 users.
okt 13 18:32:37 albert-ms7c04 rtkit-daemon[1247]: Supervising 7 threads of 2 processes of 1 users.
okt 13 18:32:37 albert-ms7c04 rtkit-daemon[1247]: Supervising 7 threads of 2 processes of 1 users.
okt 13 18:32:37 albert-ms7c04 rtkit-daemon[1247]: Successfully made thread 15498 of process 14604 owned by '1000' RT at priority 10.
okt 13 18:32:37 albert-ms7c04 rtkit-daemon[1247]: Supervising 8 threads of 3 processes of 1 users.
okt 13 18:32:37 albert-ms7c04 org_kde_powerdevil[1375]: powerdevil: Scheduling inhibition from ":1.18" "firefox" with cookie 61 and reason "audio-playing"
okt 13 18:32:37 albert-ms7c04 plasmashell[1161]: file:///usr/lib/qt/qml/QtQuick/Controls/Styles/Plasma/ToolButtonStyle.qml:196:13: QML Connections: Implicitly defined onFoo properties in Connections are deprecated. Use this syntax instead: function onFoo(<arguments>) { ... }
okt 13 18:32:37 albert-ms7c04 plasmashell[1161]: file:///usr/lib/qt/qml/QtQuick/Controls/Styles/Plasma/ToolButtonStyle.qml:196:13: QML Connections: Implicitly defined onFoo properties in Connections are deprecated. Use this syntax instead: function onFoo(<arguments>) { ... }
okt 13 18:32:38 albert-ms7c04 kernel: ata4: COMRESET failed (errno=-16)
okt 13 18:32:39 albert-ms7c04 kernel: ata4: SATA link up 6.0 Gbps (SStatus 133 SControl 300)
okt 13 18:32:39 albert-ms7c04 kernel: ata4.00: configured for UDMA/133
okt 13 18:32:42 albert-ms7c04 org_kde_powerdevil[1375]: powerdevil: Enforcing inhibition from ":1.18" "firefox" with cookie 61 and reason "audio-playing"
okt 13 18:32:42 albert-ms7c04 org_kde_powerdevil[1375]: powerdevil: Added change screen settings
okt 13 18:32:42 albert-ms7c04 org_kde_powerdevil[1375]: powerdevil: Added interrupt session
okt 13 18:32:42 albert-ms7c04 org_kde_powerdevil[1375]: powerdevil: Can't contact ck
okt 13 18:32:43 albert-ms7c04 audit[15467]: USER_AUTH pid=15467 uid=0 auid=4294967295 ses=4294967295 subj==unconfined msg='op=PAM:authentication grantors=pam_securetty,pam_shells,pam_faillock,pam_permit,pam_faillock acct="abbe" exe="/usr/bin/login" hostname=albert-ms7c04 addr=? terminal=tty2 res=success'
okt 13 18:32:43 albert-ms7c04 kernel: audit: type=1100 audit(1602606763.419:118): pid=15467 uid=0 auid=4294967295 ses=4294967295 subj==unconfined msg='op=PAM:authentication grantors=pam_securetty,pam_shells,pam_faillock,pam_permit,pam_faillock acct="abbe" exe="/usr/bin/login" hostname=albert-ms7c04 addr=? terminal=tty2 res=success'
okt 13 18:32:43 albert-ms7c04 dbus-daemon[444]: [system] Activating via systemd: service name='org.freedesktop.home1' unit='dbus-org.freedesktop.home1.service' requested by ':1.693' (uid=0 pid=15467 comm="/bin/login -p -- " label="unconfined")
okt 13 18:32:43 albert-ms7c04 dbus-daemon[444]: [system] Activation via systemd failed for unit 'dbus-org.freedesktop.home1.service': Unit dbus-org.freedesktop.home1.service not found.
okt 13 18:32:43 albert-ms7c04 login[15467]: pam_systemd_home(login:account): systemd-homed is not available: Unit dbus-org.freedesktop.home1.service not found.
okt 13 18:32:43 albert-ms7c04 audit[15467]: USER_ACCT pid=15467 uid=0 auid=4294967295 ses=4294967295 subj==unconfined msg='op=PAM:accounting grantors=pam_access,pam_permit,pam_time acct="abbe" exe="/usr/bin/login" hostname=albert-ms7c04 addr=? terminal=tty2 res=success'
okt 13 18:32:43 albert-ms7c04 audit[15467]: CRED_ACQ pid=15467 uid=0 auid=4294967295 ses=4294967295 subj==unconfined msg='op=PAM:setcred grantors=pam_securetty,pam_shells,pam_faillock,pam_permit,pam_faillock acct="abbe" exe="/usr/bin/login" hostname=albert-ms7c04 addr=? terminal=tty2 res=success'
okt 13 18:32:43 albert-ms7c04 login[15467]: pam_unix(login:session): session opened for user abbe(uid=1000) by LOGIN(uid=0)
okt 13 18:32:43 albert-ms7c04 systemd-logind[451]: New session 4 of user abbe.
░░ Subject: A new session 4 has been created for user abbe
░░ Defined-By: systemd
░░ Support: https://forum.manjaro.org/c/support
░░ Documentation: https://www.freedesktop.org/wiki/Software/systemd/multiseat
░░
░░ A new session with the ID 4 has been created for the user abbe.
░░
░░ The leading process of the session is 15467.
okt 13 18:32:43 albert-ms7c04 systemd[1]: Started Session 4 of user abbe.
░░ Subject: A start job for unit session-4.scope has finished successfully
░░ Defined-By: systemd
░░ Support: https://forum.manjaro.org/c/support
░░
░░ A start job for unit session-4.scope has finished successfully.
░░
░░ The job identifier is 1858.
okt 13 18:32:43 albert-ms7c04 kernel: audit: type=1101 audit(1602606763.423:119): pid=15467 uid=0 auid=4294967295 ses=4294967295 subj==unconfined msg='op=PAM:accounting grantors=pam_access,pam_permit,pam_time acct="abbe" exe="/usr/bin/login" hostname=albert-ms7c04 addr=? terminal=tty2 res=success'
okt 13 18:32:43 albert-ms7c04 kernel: audit: type=1103 audit(1602606763.423:120): pid=15467 uid=0 auid=4294967295 ses=4294967295 subj==unconfined msg='op=PAM:setcred grantors=pam_securetty,pam_shells,pam_faillock,pam_permit,pam_faillock acct="abbe" exe="/usr/bin/login" hostname=albert-ms7c04 addr=? terminal=tty2 res=success'
okt 13 18:32:43 albert-ms7c04 kernel: audit: type=1006 audit(1602606763.423:121): pid=15467 uid=0 subj==unconfined old-auid=4294967295 auid=1000 tty=tty2 old-ses=4294967295 ses=4 res=1
okt 13 18:32:43 albert-ms7c04 org_kde_powerdevil[1375]: powerdevil: ACTIVE SESSION PATH CHANGED: "/org/freedesktop/login1/session/_34"
okt 13 18:32:43 albert-ms7c04 audit[15467]: USER_START pid=15467 uid=0 auid=1000 ses=4 subj==unconfined msg='op=PAM:session_open grantors=pam_loginuid,pam_keyinit,pam_limits,pam_unix,pam_permit,pam_mail,pam_systemd,pam_env acct="abbe" exe="/usr/bin/login" hostname=albert-ms7c04 addr=? terminal=tty2 res=success'
okt 13 18:32:43 albert-ms7c04 audit[15467]: CRED_REFR pid=15467 uid=0 auid=1000 ses=4 subj==unconfined msg='op=PAM:setcred grantors=pam_securetty,pam_shells,pam_faillock,pam_permit,pam_faillock acct="abbe" exe="/usr/bin/login" hostname=albert-ms7c04 addr=? terminal=tty2 res=success'
okt 13 18:32:43 albert-ms7c04 org_kde_powerdevil[1375]: powerdevil: Current session is now inactive
okt 13 18:32:43 albert-ms7c04 kernel: audit: type=1105 audit(1602606763.433:122): pid=15467 uid=0 auid=1000 ses=4 subj==unconfined msg='op=PAM:session_open grantors=pam_loginuid,pam_keyinit,pam_limits,pam_unix,pam_permit,pam_mail,pam_systemd,pam_env acct="abbe" exe="/usr/bin/login" hostname=albert-ms7c04 addr=? terminal=tty2 res=success'
okt 13 18:32:43 albert-ms7c04 kernel: audit: type=1110 audit(1602606763.433:123): pid=15467 uid=0 auid=1000 ses=4 subj==unconfined msg='op=PAM:setcred grantors=pam_securetty,pam_shells,pam_faillock,pam_permit,pam_faillock acct="abbe" exe="/usr/bin/login" hostname=albert-ms7c04 addr=? terminal=tty2 res=success'
okt 13 18:32:43 albert-ms7c04 login[15467]: LOGIN ON tty2 BY abbe
okt 13 18:32:45 albert-ms7c04 org_kde_powerdevil[1375]: powerdevil: Releasing inhibition with cookie 61
okt 13 18:32:45 albert-ms7c04 plasmashell[1161]: qrc:/plasma/plasmoids/org.kde.plasma.volume/contents/ui/main.qml:482:39: QML StreamListItem: Binding loop detected for property "width"