I see what you mean, but the issue is that I haven't used any specific program for key bindings, links, shortcuts etc.. I only used system settings provided in KDE... That's the reason why I don't know where to start from, and I really don't remember at which point did this start to occur, since I installed several apps at that stage of setting up the machine, and updated all the packages several times.
~/.config/kglobalshortcutsrc
[ActivityManager]
_k_friendly_name=Activity Manager
switch-to-activity-b16c1867-b575-4915-af05-0f1ff870db20=none,none,Switch to activity "Default"
[KDE Keyboard Layout Switcher]
Switch keyboard layout to English (US)=none,none,Switch keyboard layout to English (US)
Switch keyboard layout to German (Neo qwerty)=none,none,Switch keyboard layout to German (Neo qwerty)
Switch keyboard layout to Serbian (Cyrillic, ZE and ZHE swapped)=none,none,Switch keyboard layout to Serbian (Cyrillic\\, ZE and ZHE swapped)
Switch keyboard layout to Serbian (Latin, QWERTY)=none,none,Switch keyboard layout to Serbian (Latin\\, QWERTY)
Switch to Next Keyboard Layout=Alt+X,none,Switch to Next Keyboard Layout
_k_friendly_name=KDE Daemon
[kaccess]
Toggle Screen Reader On and Off=none,Meta+Alt+S,Toggle Screen Reader On and Off
_k_friendly_name=Accessibility
[kcm_touchpad]
Disable Touchpad=Touchpad Off,Touchpad Off,Disable Touchpad
Enable Touchpad=Touchpad On,Touchpad On,Enable Touchpad
Toggle Touchpad=Touchpad Toggle,Touchpad Toggle,Toggle Touchpad
_k_friendly_name=KDE Daemon
[kded5]
Show System Activity=Ctrl+Esc,Ctrl+Esc,Show System Activity
_k_friendly_name=KDE Daemon
display=Display\tMeta+P,Display\tMeta+P,Switch Display
[khotkeys]
_k_friendly_name=KDE Daemon
{0494c9c4-8593-4653-91a8-93bd01ce0018}=none,none,Take Active Window Screenshot
{33f9c790-d5a4-4026-b937-fd6ae12354c3}=none,none,Start Screenshot Tool
{385b5046-233c-431b-a452-7d68b6cb106c}=none,none,Take Full Screen Screenshot
{70abdcc3-c859-445f-afb9-f1560ba2d34c}=none,none,Take Rectangular Region Screenshot
{aa64717a-7b6e-4160-8144-97dffa03eddf}=Ctrl+Alt+C,none,Browser
{bcb93370-037e-4e79-b3cb-2473d315d17f}=Ctrl+Alt+T,none,Launch Konsole
{d03619b6-9b3c-48cc-9d9c-a2aadb485550}=none,none,Search
[kmix]
_k_friendly_name=Audio Volume
decrease_microphone_volume=Microphone Volume Down,Microphone Volume Down,Decrease Microphone Volume
decrease_volume=Volume Down,Volume Down,Decrease Volume
increase_microphone_volume=Microphone Volume Up,Microphone Volume Up,Increase Microphone Volume
increase_volume=Volume Up,Volume Up,Increase Volume
mic_mute=Microphone Mute,Microphone Mute,Mute Microphone
mute=Volume Mute,Volume Mute,Mute
[konversation]
_k_friendly_name=Konversation
next_active_tab=none,none,Next Active Tab
toggle_mainwindow_visibility=none,none,Show/Hide Konversation
[krunner]
_k_friendly_name=Run Command
run command=Alt+Space\t\tSearch,Alt+Space,Run Command
run command on clipboard contents=Alt+Shift+F2,Alt+Shift+F2,Run Command on clipboard contents
[ksmserver]
Halt Without Confirmation=none,none,Halt Without Confirmation
Lock Session=Ctrl+Alt+L\tScreensaver,Ctrl+Alt+L\tScreensaver,Lock Session
Log Out=none,none,Log Out
Log Out Without Confirmation=none,none,Log Out Without Confirmation
Reboot Without Confirmation=none,none,Reboot Without Confirmation
_k_friendly_name=ksmserver
[kwin]
Activate Window Demanding Attention=Ctrl+Alt+A,Ctrl+Alt+A,Activate Window Demanding Attention
Decrease Opacity=none,none,Decrease Opacity of Active Window by 5 %
Expose=Ctrl+F9,Ctrl+F9,Toggle Present Windows (Current desktop)
ExposeAll=Ctrl+F10\tLaunch (C),Ctrl+F10\tLaunch (C),Toggle Present Windows (All desktops)
ExposeClass=Ctrl+F7,Ctrl+F7,Toggle Present Windows (Window class)
Increase Opacity=none,none,Increase Opacity of Active Window by 5 %
Invert Screen Colors=none,none,Invert Screen Colors
Kill Window=Ctrl+Alt+Esc,Ctrl+Alt+Esc,Kill Window
MoveMouseToCenter=Meta+F6,Meta+F6,Move Mouse to Center
MoveMouseToFocus=Meta+F5,Meta+F5,Move Mouse to Focus
MoveZoomDown=none,none,Move Zoomed Area Downwards
MoveZoomLeft=none,none,Move Zoomed Area to Left
MoveZoomRight=none,none,Move Zoomed Area to Right
MoveZoomUp=none,none,Move Zoomed Area Upwards
Remove Window From Group=none,none,Remove Window From Group
Setup Window Shortcut=none,none,Setup Window Shortcut
Show Desktop=none,none,Show Desktop
ShowDesktopGrid=Ctrl+F8,Ctrl+F8,Show Desktop Grid
Suspend Compositing=Alt+Shift+F12,Alt+Shift+F12,Suspend Compositing
Switch One Desktop Down=Meta+Ctrl+Down,none,Switch One Desktop Down
Switch One Desktop Up=Meta+Ctrl+Up,none,Switch One Desktop Up
Switch One Desktop to the Left=Meta+Ctrl+Left,none,Switch One Desktop to the Left
Switch One Desktop to the Right=Meta+Ctrl+Right,none,Switch One Desktop to the Right
Switch Window Down=Meta+Alt+Down,Meta+Alt+Down,Switch to Window Below
Switch Window Left=Meta+Alt+Left,Meta+Alt+Left,Switch to Window to the Left
Switch Window Right=Meta+Alt+Right,Meta+Alt+Right,Switch to Window to the Right
Switch Window Up=Meta+Alt+Up,Meta+Alt+Up,Switch to Window Above
Switch to Desktop 1=Ctrl+F1,Ctrl+F1,Switch to Desktop 1
Switch to Desktop 10=none,none,Switch to Desktop 10
Switch to Desktop 11=none,none,Switch to Desktop 11
Switch to Desktop 12=none,none,Switch to Desktop 12
Switch to Desktop 13=none,none,Switch to Desktop 13
Switch to Desktop 14=none,none,Switch to Desktop 14
Switch to Desktop 15=none,none,Switch to Desktop 15
Switch to Desktop 16=none,none,Switch to Desktop 16
Switch to Desktop 17=none,none,Switch to Desktop 17
Switch to Desktop 18=none,none,Switch to Desktop 18
Switch to Desktop 19=none,none,Switch to Desktop 19
Switch to Desktop 2=Ctrl+F2,Ctrl+F2,Switch to Desktop 2
Switch to Desktop 20=none,none,Switch to Desktop 20
Switch to Desktop 3=Ctrl+F3,Ctrl+F3,Switch to Desktop 3
Switch to Desktop 4=Ctrl+F4,Ctrl+F4,Switch to Desktop 4
Switch to Desktop 5=none,none,Switch to Desktop 5
Switch to Desktop 6=none,none,Switch to Desktop 6
Switch to Desktop 7=none,none,Switch to Desktop 7
Switch to Desktop 8=none,none,Switch to Desktop 8
Switch to Desktop 9=none,none,Switch to Desktop 9
Switch to Next Desktop=none,none,Switch to Next Desktop
Switch to Next Screen=none,none,Switch to Next Screen
Switch to Previous Desktop=none,none,Switch to Previous Desktop
Switch to Previous Screen=none,none,Switch to Previous Screen
Switch to Screen 0=none,none,Switch to Screen 0
Switch to Screen 1=none,none,Switch to Screen 1
Switch to Screen 2=none,none,Switch to Screen 2
Switch to Screen 3=none,none,Switch to Screen 3
Switch to Screen 4=none,none,Switch to Screen 4
Switch to Screen 5=none,none,Switch to Screen 5
Switch to Screen 6=none,none,Switch to Screen 6
Switch to Screen 7=none,none,Switch to Screen 7
Toggle Window Raise/Lower=none,none,Toggle Window Raise/Lower
Walk Through Desktop List=none,none,Walk Through Desktop List
Walk Through Desktop List (Reverse)=none,none,Walk Through Desktop List (Reverse)
Walk Through Desktops=none,none,Walk Through Desktops
Walk Through Desktops (Reverse)=none,none,Walk Through Desktops (Reverse)
Walk Through Window Tabs=none,none,Walk Through Window Tabs
Walk Through Window Tabs (Reverse)=none,none,Walk Through Window Tabs (Reverse)
Walk Through Windows=Alt+Tab,none,Walk Through Windows
Walk Through Windows (Reverse)=Alt+Shift+Tab,none,Walk Through Windows (Reverse)
Walk Through Windows Alternative=none,none,Walk Through Windows Alternative
Walk Through Windows Alternative (Reverse)=none,none,Walk Through Windows Alternative (Reverse)
Walk Through Windows of Current Application=none,none,Walk Through Windows of Current Application
Walk Through Windows of Current Application (Reverse)=none,none,Walk Through Windows of Current Application (Reverse)
Walk Through Windows of Current Application Alternative=none,none,Walk Through Windows of Current Application Alternative
Walk Through Windows of Current Application Alternative (Reverse)=none,none,Walk Through Windows of Current Application Alternative (Reverse)
Window Above Other Windows=none,none,Keep Window Above Others
Window Below Other Windows=none,none,Keep Window Below Others
Window Close=Alt+F4,Alt+F4,Close Window
Window Fullscreen=none,none,Make Window Fullscreen
Window Grow Horizontal=none,none,Pack Grow Window Horizontally
Window Grow Vertical=none,none,Pack Grow Window Vertically
Window Lower=none,none,Lower Window
Window Maximize=Meta+PgUp,Meta+PgUp,Maximize Window
Window Maximize Horizontal=none,none,Maximize Window Horizontally
Window Maximize Vertical=none,none,Maximize Window Vertically
Window Minimize=Meta+PgDown,Meta+PgDown,Minimize Window
Window Move=none,none,Move Window
Window No Border=none,none,Hide Window Border
Window On All Desktops=none,none,Keep Window on All Desktops
Window One Desktop Down=Meta+Ctrl+Alt+Down,none,Window One Desktop Down
Window One Desktop Up=Meta+Ctrl+Alt+Up,none,Window One Desktop Up
Window One Desktop to the Left=Meta+Ctrl+Alt+Left,none,Window One Desktop to the Left
Window One Desktop to the Right=Meta+Ctrl+Alt+Right,none,Window One Desktop to the Right
Window Operations Menu=Alt+F3,Alt+F3,Window Operations Menu
Window Pack Down=none,none,Pack Window Down
Window Pack Left=none,none,Pack Window to the Left
Window Pack Right=none,none,Pack Window to the Right
Window Pack Up=none,none,Pack Window Up
Window Quick Tile Bottom=Meta+Down,Meta+Down,Quick Tile Window to the Bottom
Window Quick Tile Bottom Left=none,none,Quick Tile Window to the Bottom Left
Window Quick Tile Bottom Right=none,none,Quick Tile Window to the Bottom Right
Window Quick Tile Left=Meta+Left,Meta+Left,Quick Tile Window to the Left
Window Quick Tile Right=Meta+Right,Meta+Right,Quick Tile Window to the Right
Window Quick Tile Top=Meta+Up,Meta+Up,Quick Tile Window to the Top
Window Quick Tile Top Left=none,none,Quick Tile Window to the Top Left
Window Quick Tile Top Right=none,none,Quick Tile Window to the Top Right
Window Raise=none,none,Raise Window
Window Resize=none,none,Resize Window
Window Shade=none,none,Shade Window
Window Shrink Horizontal=none,none,Pack Shrink Window Horizontally
Window Shrink Vertical=none,none,Pack Shrink Window Vertically
Window to Desktop 1=none,none,Window to Desktop 1
Window to Desktop 10=none,none,Window to Desktop 10
Window to Desktop 11=none,none,Window to Desktop 11
Window to Desktop 12=none,none,Window to Desktop 12
Window to Desktop 13=none,none,Window to Desktop 13
Window to Desktop 14=none,none,Window to Desktop 14
Window to Desktop 15=none,none,Window to Desktop 15
Window to Desktop 16=none,none,Window to Desktop 16
Window to Desktop 17=none,none,Window to Desktop 17
Window to Desktop 18=none,none,Window to Desktop 18
Window to Desktop 19=none,none,Window to Desktop 19
Window to Desktop 2=none,none,Window to Desktop 2
Window to Desktop 20=none,none,Window to Desktop 20
Window to Desktop 3=none,none,Window to Desktop 3
Window to Desktop 4=none,none,Window to Desktop 4
Window to Desktop 5=none,none,Window to Desktop 5
Window to Desktop 6=none,none,Window to Desktop 6
Window to Desktop 7=none,none,Window to Desktop 7
Window to Desktop 8=none,none,Window to Desktop 8
Window to Desktop 9=none,none,Window to Desktop 9
Window to Next Desktop=none,none,Window to Next Desktop
Window to Next Screen=none,none,Window to Next Screen
Window to Previous Desktop=none,none,Window to Previous Desktop
Window to Previous Screen=none,none,Window to Previous Screen
Window to Screen 0=none,none,Window to Screen 0
Window to Screen 1=none,none,Window to Screen 1
Window to Screen 2=none,none,Window to Screen 2
Window to Screen 3=none,none,Window to Screen 3
Window to Screen 4=none,none,Window to Screen 4
Window to Screen 5=none,none,Window to Screen 5
Window to Screen 6=none,none,Window to Screen 6
Window to Screen 7=none,none,Window to Screen 7
_k_friendly_name=KWin
view_actual_size=,Meta+0,Actual Size
view_zoom_in=Meta+=,Meta+=,Zoom In
view_zoom_out=Meta+-,Meta+-,Zoom Out
[mediacontrol]
_k_friendly_name=Media Controller
mediavolumedown=none,none,Media volume down
mediavolumeup=none,none,Media volume up
nextmedia=Media Next,Media Next,Media playback next
playpausemedia=Media Play,Media Play,Play/Pause media playback
previousmedia=Media Previous,Media Previous,Media playback previous
stopmedia=Media Stop,Media Stop,Stop media playback
[org_kde_powerdevil]
Decrease Keyboard Brightness=Keyboard Brightness Down,Keyboard Brightness Down,Decrease Keyboard Brightness
Decrease Screen Brightness=Monitor Brightness Down,Monitor Brightness Down,Decrease Screen Brightness
Hibernate=Hibernate,Hibernate,Hibernate
Increase Keyboard Brightness=Keyboard Brightness Up,Keyboard Brightness Up,Increase Keyboard Brightness
Increase Screen Brightness=Monitor Brightness Up,Monitor Brightness Up,Increase Screen Brightness
PowerOff=Power Off,Power Off,Power Off
Sleep=Sleep,Sleep,Suspend
Toggle Keyboard Backlight=Keyboard Light On/Off,Keyboard Light On/Off,Toggle Keyboard Backlight
_k_friendly_name=Power Management
[plasmashell]
_k_friendly_name=Plasma
activate task manager entry 1=Meta+1,Meta+1,Activate Task Manager Entry 1
activate task manager entry 10=Meta+0,Meta+0,Activate Task Manager Entry 10
activate task manager entry 2=Meta+2,Meta+2,Activate Task Manager Entry 2
activate task manager entry 3=Meta+3,Meta+3,Activate Task Manager Entry 3
activate task manager entry 4=Meta+4,Meta+4,Activate Task Manager Entry 4
activate task manager entry 5=Meta+5,Meta+5,Activate Task Manager Entry 5
activate task manager entry 6=Meta+6,Meta+6,Activate Task Manager Entry 6
activate task manager entry 7=Meta+7,Meta+7,Activate Task Manager Entry 7
activate task manager entry 8=Meta+8,Meta+8,Activate Task Manager Entry 8
activate task manager entry 9=Meta+9,Meta+9,Activate Task Manager Entry 9
activate widget 2=Alt+F1,none,Activate Application Launcher Widget
clear-history=none,none,Clear Clipboard History
clipboard_action=none,Ctrl+Alt+X,Enable Clipboard Actions
cycleNextAction=none,none,Next History Item
cyclePrevAction=none,none,Previous History Item
edit_clipboard=none,none,Edit Contents...
manage activities=Meta+Q,Meta+Q,Activities...
next activity=none,none,Walk through activities
previous activity=none,none,Walk through activities (Reverse)
repeat_action=none,Ctrl+Alt+R,Manually Invoke Action on Current Clipboard
show dashboard=Ctrl+F12,Ctrl+F12,Show Desktop
show-barcode=none,none,Show Barcode...
show-on-mouse-pos=none,none,Open Klipper at Mouse Position
stop current activity=Meta+S,Meta+S,Stop Current Activity
[yakuake]
_k_friendly_name=Yakuake
toggle-window-state=F12,F12,Open/Retract Yakuake