Ubuntu – Unable to use keyboard shortcut combination including Alt+Shift

Summary

Any shortcut combination involving Alt+Shift is not picked up. When I try to set (or use) shortcuts in PhpStorm that involve Alt+Shift nothing happens. I thought to start with it only affects PhpStorm but when I try to set those shortcuts in my terminal the keys are not working either. I already tried remove all Alt+Shift shortcut combinations from the system shortcuts that I could find but that didn't help either.
It seems to only affect my external keyboard if using the internal keyboard of the laptop it works just fine. So I tried a different keyboard (CORSAIR STRAFE RGB MK.2 Mechanical Gaming Keyboard) and with that one it works just fine.

Setup

Lenovo ThinkPad L490
Ubuntu 20.04.1 LTS
GNOME Shell 3.36.4
Keyboard: Sharkoon Skiller Pro

My laptop is connected to a USB-C Triple-4K Dock from Displaylink. The external keyboard is connected to a USB switch which is connected to the docking station. I tried to plug the keyboard in the docking station and in the laptop directly but it didn't change anything.

The output of lsusb:

Bus 002 Device 006: ID 05e3:0620 Genesys Logic, Inc. 
Bus 002 Device 005: ID 2109:0813 VIA Labs, Inc. 
Bus 002 Device 004: ID 2109:0210 VIA Labs, Inc. 
Bus 002 Device 003: ID 17e9:6000 DisplayLink USB3.0 Hub
Bus 002 Device 002: ID 2109:0813 VIA Labs, Inc. USB3.0 Hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 015: ID 2cb7:0210 FIBOCOM L830-EB
Bus 001 Device 008: ID 27c6:55b4 Shenzhen Goodix Technology Co.,Ltd. Fingerprint Reader
Bus 001 Device 006: ID 13d3:56bc IMC Networks Integrated Camera
Bus 001 Device 005: ID 8087:0025 Intel Corp. 
Bus 001 Device 003: ID 058f:9540 Alcor Micro Corp. AU9540 Smartcard Reader
Bus 001 Device 012: ID 1038:12ad SteelSeries ApS 
Bus 001 Device 014: ID 04d9:a096 Holtek Semiconductor, Inc. Keyboard
Bus 001 Device 013: ID 046d:c332 Logitech, Inc. G502 Proteus Spectrum Optical Mouse
Bus 001 Device 010: ID 05e3:0610 Genesys Logic, Inc. 4-port hub
Bus 001 Device 007: ID 2109:2813 VIA Labs, Inc. USB2.0 Hub
Bus 001 Device 009: ID 10c4:f608 Silicon Labs 
Bus 001 Device 004: ID 2109:2210 VIA Labs, Inc. 
Bus 001 Device 002: ID 2109:2813 VIA Labs, Inc. USB2.0 Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

Current shortcuts including either Alt or Shift

These are all the shortcuts using either Alt or Shift:

$ gsettings list-recursively | grep '<Alt>'
org.gnome.desktop.wm.keybindings switch-group ['<Super>Above_Tab', '<Alt>Above_Tab']
org.gnome.desktop.wm.keybindings toggle-maximized ['<Alt>F10']
org.gnome.desktop.wm.keybindings cycle-windows ['<Alt>Escape']
org.gnome.desktop.wm.keybindings activate-window-menu ['<Alt>space']
org.gnome.desktop.wm.keybindings panel-main-menu ['<Alt>F1']
org.gnome.desktop.wm.keybindings close ['<Alt>F4']
org.gnome.desktop.wm.keybindings switch-windows ['<Alt>Tab']
org.gnome.desktop.wm.keybindings panel-run-dialog ['<Alt>F2']
org.gnome.desktop.wm.keybindings unmaximize ['<Super>Down', '<Alt>F5']
org.gnome.desktop.wm.keybindings show-desktop ['<Primary><Super>d', '<Primary><Alt>d', '<Super>d']
org.gnome.desktop.wm.keybindings cycle-group ['<Alt>F6']
org.gnome.mutter.wayland.keybindings switch-to-session-4 ['<Primary><Alt>F4']
org.gnome.mutter.wayland.keybindings switch-to-session-10 ['<Primary><Alt>F10']
org.gnome.mutter.wayland.keybindings switch-to-session-3 ['<Primary><Alt>F3']
org.gnome.mutter.wayland.keybindings switch-to-session-9 ['<Primary><Alt>F9']
org.gnome.mutter.wayland.keybindings switch-to-session-2 ['<Primary><Alt>F2']
org.gnome.mutter.wayland.keybindings switch-to-session-8 ['<Primary><Alt>F8']
org.gnome.mutter.wayland.keybindings switch-to-session-1 ['<Primary><Alt>F1']
org.gnome.mutter.wayland.keybindings switch-to-session-7 ['<Primary><Alt>F7']
org.gnome.mutter.wayland.keybindings switch-to-session-12 ['<Primary><Alt>F12']
org.gnome.mutter.wayland.keybindings switch-to-session-6 ['<Primary><Alt>F6']
org.gnome.mutter.wayland.keybindings switch-to-session-11 ['<Primary><Alt>F11']
org.gnome.mutter.wayland.keybindings switch-to-session-5 ['<Primary><Alt>F5']
org.gnome.settings-daemon.plugins.media-keys magnifier-zoom-in ['<Alt><Super>equal']
org.gnome.settings-daemon.plugins.media-keys volume-mute-quiet-static ['<Alt>XF86AudioMute']
org.gnome.settings-daemon.plugins.media-keys magnifier-zoom-out ['<Alt><Super>minus']
org.gnome.settings-daemon.plugins.media-keys volume-down-quiet-static ['<Alt>XF86AudioLowerVolume']
org.gnome.settings-daemon.plugins.media-keys window-screenshot ['<Alt>Print']
org.gnome.settings-daemon.plugins.media-keys terminal ['<Primary><Alt>t']
org.gnome.settings-daemon.plugins.media-keys volume-up-quiet-static ['<Alt>XF86AudioRaiseVolume']
org.gnome.settings-daemon.plugins.media-keys screenreader ['<Alt><Super>s']
org.gnome.settings-daemon.plugins.media-keys magnifier ['<Alt><Super>8']
org.gnome.Terminal.Legacy.Keybindings switch-to-tab-2 '<Alt>2'
org.gnome.Terminal.Legacy.Keybindings switch-to-tab-3 '<Alt>3'
org.gnome.Terminal.Legacy.Keybindings switch-to-tab-4 '<Alt>4'
org.gnome.Terminal.Legacy.Keybindings switch-to-tab-5 '<Alt>5'
org.gnome.Terminal.Legacy.Keybindings switch-to-tab-6 '<Alt>6'
org.gnome.Terminal.Legacy.Keybindings switch-to-tab-7 '<Alt>7'
org.gnome.Terminal.Legacy.Keybindings switch-to-tab-8 '<Alt>8'
org.gnome.Terminal.Legacy.Keybindings switch-to-tab-9 '<Alt>9'
org.gnome.Terminal.Legacy.Keybindings switch-to-tab-10 '<Alt>0'
org.gnome.Terminal.Legacy.Keybindings switch-to-tab-1 '<Alt>1'
$ gsettings list-recursively | grep '<Shift>'
org.gnome.desktop.wm.keybindings move-to-monitor-right ['<Super><Shift>Right']
org.gnome.desktop.wm.keybindings move-to-workspace-1 ['<Super><Shift>Home']
org.gnome.desktop.wm.keybindings move-to-monitor-left ['<Super><Shift>Left']
org.gnome.desktop.wm.keybindings switch-applications-backward ['<Shift><Super>Tab']
org.gnome.desktop.wm.keybindings switch-input-source-backward ['<Shift><Super>space', '<Shift>XF86Keyboard']
org.gnome.desktop.wm.keybindings move-to-monitor-down ['<Super><Shift>Down']
org.gnome.desktop.wm.keybindings move-to-workspace-last ['<Super><Shift>End']
org.gnome.desktop.wm.keybindings switch-group-backward ['<Shift><Super>Above_Tab']
org.gnome.settings-daemon.plugins.media-keys area-screenshot ['<Shift>Print']
org.gnome.settings-daemon.plugins.media-keys volume-up-precise-static ['<Shift>XF86AudioRaiseVolume']
org.gnome.settings-daemon.plugins.media-keys volume-down-precise-static ['<Shift>XF86AudioLowerVolume']
org.gnome.shell.extensions.dash-to-dock app-shift-hotkey-1 ['<Shift><Super>1']
org.gnome.shell.extensions.dash-to-dock app-shift-hotkey-2 ['<Shift><Super>2']
org.gnome.shell.extensions.dash-to-dock app-shift-hotkey-3 ['<Shift><Super>3']
org.gnome.shell.extensions.dash-to-dock app-shift-hotkey-4 ['<Shift><Super>4']
org.gnome.shell.extensions.dash-to-dock app-shift-hotkey-5 ['<Shift><Super>5']
org.gnome.shell.extensions.dash-to-dock app-shift-hotkey-6 ['<Shift><Super>6']
org.gnome.shell.extensions.dash-to-dock app-shift-hotkey-7 ['<Shift><Super>7']
org.gnome.shell.extensions.dash-to-dock app-shift-hotkey-8 ['<Shift><Super>8']
org.gnome.shell.extensions.dash-to-dock app-shift-hotkey-9 ['<Shift><Super>9']
org.gnome.shell.extensions.dash-to-dock app-shift-hotkey-10 ['<Shift><Super>0']
org.gnome.Terminal.Legacy.Keybindings close-window '<Ctrl><Shift>q'
org.gnome.Terminal.Legacy.Keybindings find-previous '<Control><Shift>H'
org.gnome.Terminal.Legacy.Keybindings new-tab '<Ctrl><Shift>t'
org.gnome.Terminal.Legacy.Keybindings close-tab '<Ctrl><Shift>w'
org.gnome.Terminal.Legacy.Keybindings find '<Control><Shift>F'
org.gnome.Terminal.Legacy.Keybindings find-next '<Control><Shift>G'
org.gnome.Terminal.Legacy.Keybindings move-tab-right '<Ctrl><Shift>Page_Down'
org.gnome.Terminal.Legacy.Keybindings move-tab-left '<Ctrl><Shift>Page_Up'
org.gnome.Terminal.Legacy.Keybindings new-window '<Ctrl><Shift>n'
org.gnome.Terminal.Legacy.Keybindings paste '<Ctrl><Shift>v'
org.gnome.Terminal.Legacy.Keybindings copy '<Ctrl><Shift>c'
org.gnome.Terminal.Legacy.Keybindings find-clear '<Control><Shift>J'

Device grabs

So it seems to me that no system shortcuts could block the combination and I tried to figure out which program is catching the combination based on this answer:

$ KEY=shift+alt
$ xdotool keydown ${KEY}; xdotool key XF86LogGrabInfo; xdotool keyup ${KEY}

Gives me

/usr/lib/gdm3/gdm-x-session[2600]: (II) Printing all currently active device grabs:
/usr/lib/gdm3/gdm-x-session[2600]: (II) End list of active device grabs
/usr/lib/gdm3/gdm-x-session[2600]: Printing all currently registered grabs
/usr/lib/gdm3/gdm-x-session[2600]:   Printing all registered grabs of client pid 2504 /usr/bin/pulseaudio --daemonize=no --log-target=journal
/usr/lib/gdm3/gdm-x-session[2600]:   Printing all registered grabs of client pid 2810 /usr/bin/gnome-shell
/usr/lib/gdm3/gdm-x-session[2600]:   grab 0x40409425 (xi2), type 'ButtonPress' on window 0x3603505
/usr/lib/gdm3/gdm-x-session[2600]:     detail 3 (mask 0), modifiersDetail 78 (mask 0)
/usr/lib/gdm3/gdm-x-session[2600]:     device 'Virtual core pointer' (2), modifierDevice 'Virtual core keyboard' (3)
/usr/lib/gdm3/gdm-x-session[2600]:       xi2 event mask 0x70 0 0 0
/usr/lib/gdm3/gdm-x-session[2600]:     owner-events false, kb 1 ptr 1, confine 0x0, cursor 0x0
[...]
/usr/lib/gdm3/gdm-x-session[2600]: End list of registered passive grabs

At [...] it first continues a long list of gabs like the one you can see and then simply list "Printing all registered grabs…" of other programs running but they to not have any grabs. What I am wondering is why it shows only passive grabs and not a single active grab… I tried that with different Alt+Shift combinations like Ctrl+Alt+Shift+N with the same result.

I tried xev to verify the key presses are picked up and that my keyboard is not broken. This is the output when pressing Alt+Shift:

KeyPress event, serial 33, synthetic NO, window 0x3a00001,
    root 0x67c, subw 0x0, time 5260869, (617,537), root:(5135,612),
    state 0x10, keycode 64 (keysym 0xffe9, Alt_L), same_screen YES,
    XLookupString gives 0 bytes: 
    XmbLookupString gives 0 bytes: 
    XFilterEvent returns: False

KeyPress event, serial 36, synthetic NO, window 0x3a00001,
    root 0x67c, subw 0x0, time 5261309, (617,537), root:(5135,612),
    state 0x18, keycode 50 (keysym 0xffe1, Shift_L), same_screen YES,
    XLookupString gives 0 bytes: 
    XmbLookupString gives 0 bytes: 
    XFilterEvent returns: False

KeyRelease event, serial 36, synthetic NO, window 0x3a00001,
    root 0x67c, subw 0x0, time 5261509, (617,537), root:(5135,612),
    state 0x19, keycode 50 (keysym 0xffe1, Shift_L), same_screen YES,
    XLookupString gives 0 bytes: 
    XFilterEvent returns: False

KeyRelease event, serial 36, synthetic NO, window 0x3a00001,
    root 0x67c, subw 0x0, time 5261821, (617,537), root:(5135,612),
    state 0x18, keycode 64 (keysym 0xffe9, Alt_L), same_screen YES,
    XLookupString gives 0 bytes: 
    XFilterEvent returns: False

Keyboard configuration

This is the output of cat /etc/default/keyboard | grep -v ^# | sort -u:

$ cat /etc/default/keyboard | grep -v ^# | sort -u

BACKSPACE="guess"
XKBLAYOUT="de"
XKBMODEL="pc105"
XKBOPTIONS=""
XKBVARIANT=""

Input source configuration

Here the configuration for changing the layout in the GUI:

An here the gsettings:

$ gsettings list-recursively | grep switch-input-source
org.gnome.desktop.wm.keybindings switch-input-source ['<Super>space', 'XF86Keyboard']
org.gnome.desktop.wm.keybindings switch-input-source-backward ['<Shift><Super>space', '<Shift>XF86Keyboard']

Output of dmesg

As of Alex idea that it might be a driver issue I had a look with dmesg to see what is going on when plugging in the keyboard. This is the output:

[ 7493.338217] usb 1-4.4.2.4: new full-speed USB device number 21 using xhci_hcd
[ 7493.470386] usb 1-4.4.2.4: New USB device found, idVendor=04d9, idProduct=a096, bcdDevice= 2.07
[ 7493.470389] usb 1-4.4.2.4: New USB device strings: Mfr=0, Product=2, SerialNumber=0
[ 7493.470390] usb 1-4.4.2.4: Product: USB Keyboard
[ 7493.483050] input: USB Keyboard as /devices/pci0000:00/0000:00:14.0/usb1/1-4/1-4.4/1-4.4.2/1-4.4.2.4/1-4.4.2.4:1.0/0003:04D9:A096.0013/input/input58
[ 7493.542670] hid-generic 0003:04D9:A096.0013: input,hidraw4: USB HID v1.11 Keyboard [USB Keyboard] on usb-0000:00:14.0-4.4.2.4/input0
[ 7493.550684] input: USB Keyboard as /devices/pci0000:00/0000:00:14.0/usb1/1-4/1-4.4/1-4.4.2/1-4.4.2.4/1-4.4.2.4:1.1/0003:04D9:A096.0014/input/input59
[ 7493.609914] input: USB Keyboard System Control as /devices/pci0000:00/0000:00:14.0/usb1/1-4/1-4.4/1-4.4.2/1-4.4.2.4/1-4.4.2.4:1.1/0003:04D9:A096.0014/input/input60
[ 7493.610001] input: USB Keyboard Consumer Control as /devices/pci0000:00/0000:00:14.0/usb1/1-4/1-4.4/1-4.4.2/1-4.4.2.4/1-4.4.2.4:1.1/0003:04D9:A096.0014/input/input61
[ 7493.610132] hid-generic 0003:04D9:A096.0014: input,hiddev3,hidraw5: USB HID v1.11 Keyboard [USB Keyboard] on usb-0000:00:14.0-4.4.2.4/input1
[ 7493.612256] hid-generic 0003:04D9:A096.0015: hiddev4,hidraw6: USB HID v1.11 Device [USB Keyboard] on usb-0000:00:14.0-4.4.2.4/input2
[ 7493.671407] audit: type=1107 audit(1610529563.508:151): pid=1061 uid=103 auid=4294967295 ses=4294967295 subj=unconfined msg='apparmor="DENIED" operation="dbus_signal"  bus="system" path="/org/freedesktop/NetworkManager" interface="org.freedesktop.NetworkManager" member="CheckPermissions" name=":1.10" mask="receive" pid=15025 label="snap.spotify.spotify" peer_pid=1062 peer_label="unconfined"
                exe="/usr/bin/dbus-daemon" sauid=103 hostname=? addr=? terminal=?'
[ 7493.677617] audit: type=1107 audit(1610529563.512:152): pid=1061 uid=103 auid=4294967295 ses=4294967295 subj=unconfined msg='apparmor="DENIED" operation="dbus_signal"  bus="system" path="/org/freedesktop/NetworkManager" interface="org.freedesktop.NetworkManager" member="CheckPermissions" name=":1.10" mask="receive" pid=15025 label="snap.spotify.spotify" peer_pid=1062 peer_label="unconfined"
                exe="/usr/bin/dbus-daemon" sauid=103 hostname=? addr=? terminal=?'
[ 7493.680298] hid-generic 0003:04D9:A096.0013: implement() called with too large value 1 (n: 0)! (kworker/6:1)
[ 7493.680338] ------------[ cut here ]------------
[ 7493.680344] WARNING: CPU: 6 PID: 21154 at drivers/hid/hid-core.c:1422 implement.cold+0x5e/0x68 [hid]
[ 7493.680344] Modules linked in: xt_nat xt_tcpudp veth rfcomm xt_conntrack xt_MASQUERADE nf_conntrack_netlink nfnetlink xfrm_user xfrm_algo xt_addrtype iptable_filter iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 libcrc32c bpfilter br_netfilter bridge stp llc aufs cmac algif_hash algif_skcipher af_alg overlay bnep nls_iso8859_1 mei_hdcp snd_sof_pci snd_sof_intel_byt snd_sof_intel_ipc snd_sof_intel_hda_common x86_pkg_temp_thermal intel_powerclamp snd_hda_codec_hdmi coretemp intel_rapl_msr snd_soc_hdac_hda snd_sof_xtensa_dsp snd_sof_intel_hda kvm_intel snd_sof snd_hda_ext_core snd_hda_codec_realtek snd_soc_acpi_intel_match snd_soc_acpi snd_hda_codec_generic kvm iwlmvm rapl snd_soc_core mac80211 snd_compress intel_cstate ac97_bus snd_pcm_dmaengine snd_hda_intel libarc4 serio_raw efi_pstore wmi_bmof intel_wmi_thunderbolt snd_intel_dspcfg elan_i2c ee1004 iwlwifi snd_hda_codec mei_me thinkpad_acpi cdc_mbim snd_hda_core cdc_wdm mei nvram cfg80211 ledtrig_audio snd_usb_audio btusb
[ 7493.680361]  snd_usbmidi_lib btrtl snd_hwdep btbcm uvcvideo snd_seq_midi btintel snd_seq_midi_event videobuf2_vmalloc videobuf2_memops input_leds bluetooth snd_rawmidi videobuf2_v4l2 videobuf2_common snd_seq snd_pcm cdc_ncm videodev joydev usbnet snd_seq_device ecdh_generic cdc_acm ecc mii snd_timer mc processor_thermal_device intel_rapl_common snd intel_soc_dts_iosf ucsi_acpi typec_ucsi int3403_thermal intel_pch_thermal typec soundcore int340x_thermal_zone int3400_thermal acpi_thermal_rel acpi_pad mac_hid sch_fq_codel evdi(O) parport_pc ppdev lp parport ip_tables x_tables autofs4 dm_crypt hid_generic usbhid hid i915 crct10dif_pclmul crc32_pclmul ghash_clmulni_intel i2c_algo_bit aesni_intel drm_kms_helper rtsx_pci_sdmmc crypto_simd syscopyarea cryptd sysfillrect glue_helper sysimgblt fb_sys_fops cec e1000e rc_core psmouse drm intel_lpss_pci nvme i2c_i801 i2c_smbus intel_lpss rtsx_pci idma64 nvme_core xhci_pci virt_dma xhci_pci_renesas wmi pinctrl_cannonlake video pinctrl_intel
[ 7493.680388] CPU: 6 PID: 21154 Comm: kworker/6:1 Tainted: G        W  O      5.8.0-36-generic #40~20.04.1-Ubuntu
[ 7493.680388] Hardware name: LENOVO 20Q500E2GE/20Q500E2GE, BIOS R0ZET31W (1.09 ) 07/01/2019
[ 7493.680391] Workqueue: events hidinput_led_worker [hid]
[ 7493.680394] RIP: 0010:implement.cold+0x5e/0x68 [hid]
[ 7493.680395] Code: c7 d0 18 00 00 89 d9 48 c7 c2 c8 f3 0f c0 65 48 8b 04 25 c0 7b 01 00 48 c7 c6 10 93 10 c0 4c 8d 88 98 0a 00 00 e8 eb 6f c8 cd <0f> 0b 44 21 fb e9 22 4d ff ff 48 c7 c6 08 69 10 c0 48 c7 c7 48 93
[ 7493.680395] RSP: 0018:ffffaf2045213d28 EFLAGS: 00010046
[ 7493.680396] RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000
[ 7493.680397] RDX: ffff97b1d05a9020 RSI: ffff97b1d0598cd0 RDI: ffff97b1d0598cd0
[ 7493.680397] RBP: ffffaf2045213d50 R08: ffff97b1d0598cd0 R09: 0000000000000004
[ 7493.680398] R10: 0000000000000000 R11: 0000000000000001 R12: ffff97b1c65b1f40
[ 7493.680398] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
[ 7493.680399] FS:  0000000000000000(0000) GS:ffff97b1d0580000(0000) knlGS:0000000000000000
[ 7493.680399] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 7493.680400] CR2: 00007f07d231a570 CR3: 00000007b0886006 CR4: 00000000003606e0
[ 7493.680400] Call Trace:
[ 7493.680404]  hid_output_report+0x123/0x160 [hid]
[ 7493.680407]  usbhid_submit_report+0xf7/0x3a0 [usbhid]
[ 7493.680408]  usbhid_request+0x1a/0x30 [usbhid]
[ 7493.680410]  hidinput_led_worker+0x51/0x120 [hid]
[ 7493.680413]  ? bpf_jit_free+0x1c/0x60
[ 7493.680414]  process_one_work+0x1e8/0x3b0
[ 7493.680415]  worker_thread+0x4d/0x3f0
[ 7493.680417]  kthread+0x114/0x150
[ 7493.680418]  ? process_one_work+0x3b0/0x3b0
[ 7493.680419]  ? kthread_park+0x90/0x90
[ 7493.680421]  ret_from_fork+0x1f/0x30
[ 7493.680422] ---[ end trace 679a9ff0894011b5 ]---
[ 7493.688081] audit: type=1107 audit(1610529563.524:153): pid=1061 uid=103 auid=4294967295 ses=4294967295 subj=unconfined msg='apparmor="DENIED" operation="dbus_signal"  bus="system" path="/org/freedesktop/NetworkManager" interface="org.freedesktop.NetworkManager" member="CheckPermissions" name=":1.10" mask="receive" pid=15025 label="snap.spotify.spotify" peer_pid=1062 peer_label="unconfined"
                exe="/usr/bin/dbus-daemon" sauid=103 hostname=? addr=? terminal=?'
[ 7493.765131] audit: type=1107 audit(1610529563.600:154): pid=1061 uid=103 auid=4294967295 ses=4294967295 subj=unconfined msg='apparmor="DENIED" operation="dbus_signal"  bus="system" path="/org/freedesktop/NetworkManager" interface="org.freedesktop.NetworkManager" member="CheckPermissions" name=":1.10" mask="receive" pid=15025 label="snap.spotify.spotify" peer_pid=1062 peer_label="unconfined"
                exe="/usr/bin/dbus-daemon" sauid=103 hostname=? addr=? terminal=?'

Everything between [ cut here ] and [end trace ] does not happen when I plugin the other keyboard.

Additional Info

As Quasímodo suggested in the comments it might be gnome interfering so I installed icewm and tried to set an Alt+Shift for my terminal, unsuccessfully. I did try to use XF86LogGrabInfo like above but with the same result, all passive grabs (a lot of them again) where made from the icewm shell.

How can I figure out what blocks Alt+Shift combinations?