mjhjmtu

Ctrl-t Doesn't open new tab in dolphin and chrome, doesn't go back to the previous place with vim ctags/cscope. It's okay in tty login terminal.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma:
(available in About System)
KDE Plasma Version: 5.13.5-1+b1
KDE Frameworks Version: KDE Frameworks 5.49.0
Qt Version: Qt 5.11.2 (built against 5.11.2)


ADDITIONAL INFORMATION
The xcb windowing system
Konsole: Version 18.04.0
Dolphin: Version 18.08.0
chrome: Version 70.0.3538.102 (Official Build) (64-bit)

ii kdeplasma-addons-data 4:5.13.5-1 all locale files for kdeplasma-addons
ii libkdeclarative5 4:4.14.38-2 amd64 declarative library for plasma
ii libkf5plasma5:amd64 5.49.0-1 amd64 Plasma Runtime components
ii libkf5plasmaquick5:amd64 5.49.0-1 amd64 Plasma Runtime components
rc libplasma-geolocation-interface4 4:4.11.13-2 amd64 library for the Plasma geolocation
ii libplasma-geolocation-interface5 4:5.13.5-1+b1 amd64 Plasma Workspace for KF5 library
ii libplasma3 4:4.14.38-2 amd64 Plasma Library for the KDE Platform
rc libplasmaclock4abi4 4:4.11.13-2 amd64 library for Plasma clocks
rc libplasmagenericshell4 4:4.11.13-2 amd64 shared elements for all the plasma shells
rc libsmokeplasma3 4:4.14.2-1 amd64 Plasma SMOKE library
rc plasma-containments-addons 4:4.14.2-1 amd64 additional containment plugins for Plasma
ii plasma-dataengines-addons 4:5.13.5-1 amd64 additional data engines for Plasma
ii plasma-desktop 4:5.13.5-1+b1 amd64 Tools and widgets for the desktop
ii plasma-desktop-data 4:5.13.5-1 all Tools and widgets for the desktop data files
rc plasma-discover 5.12.4-2 amd64 Discover software management suite
rc plasma-discover-common 5.12.4-2 all Discover software manager suite (common data files)
ii plasma-framework 5.49.0-1 amd64 Plasma Runtime components
ii plasma-integration 5.13.5-1+b1 amd64 Qt Platform Theme integration plugins for KDE Plasma
ii plasma-nm 4:5.13.5-1 amd64 Plasma5 networkmanager library.
ii plasma-pa 4:5.13.4-1 amd64 Plasma 5 Volume controller
ii plasma-runners-addons 4:5.13.5-1 amd64 additional runners for Plasma 5 and Krunner
ii plasma-scriptengine-javascript 4:17.08.3-2 amd64 JavaScript script engine for Plasma
rc plasma-scriptengine-superkaramba 4:4.14.2-1 amd64 SuperKaramba theme support for the Plasma Workspaces
ii plasma-wallpapers-addons 4:5.13.5-1 amd64 additional wallpaper plugins for Plasma 5
rc plasma-widget-lancelot 4:4.14.2-1 amd64 lancelot widget for Plasma
rc plasma-widgets-addons 4:5.12.4-1 amd64 additional widgets for Plasma 5
rc plasma-widgets-workspace 4:4.11.13-2 amd64 plasma widgets and containments for the KDE Plasma Workspace
ii plasma-workspace 4:5.13.5-1+b1 amd64 Plasma Workspace for KF5

xev doesn't show the 't' code when combined with ctrl, the others are okay:

ctrl-f's key series:

KeyPress event, serial 40, synthetic NO, window 0x5000001,
 root 0x13f, subw 0x0, time 27644889, (868,396), root:(868,420),
 state 0x0, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
 XLookupString gives 0 bytes:
 XmbLookupString gives 0 bytes:
 XFilterEvent returns: False

KeyPress event, serial 40, synthetic NO, window 0x5000001,
 root 0x13f, subw 0x0, time 27645037, (868,396), root:(868,420),
 state 0x4, keycode 41 (keysym 0x66, f), same_screen YES,
 XLookupString gives 1 bytes: (06) ""
 XmbLookupString gives 1 bytes: (06) ""
 XFilterEvent returns: False

KeyRelease event, serial 40, synthetic NO, window 0x5000001,
 root 0x13f, subw 0x0, time 27645112, (868,396), root:(868,420),
 state 0x4, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
 XLookupString gives 0 bytes:
 XFilterEvent returns: False

KeyRelease event, serial 40, synthetic NO, window 0x5000001,
 root 0x13f, subw 0x0, time 27645117, (868,396), root:(868,420),
 state 0x0, keycode 41 (keysym 0x66, f), same_screen YES,
 XLookupString gives 1 bytes: (66) "f"
 XFilterEvent returns: False

ctrl-t's:

KeyPress event, serial 40, synthetic NO, window 0x5000001,
 root 0x13f, subw 0x0, time 27812868, (223,341), root:(223,365),
 state 0x0, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
 XLookupString gives 0 bytes:
 XmbLookupString gives 0 bytes:
 XFilterEvent returns: False

FocusOut event, serial 40, synthetic NO, window 0x5000001,
 mode NotifyGrab, detail NotifyAncestor

FocusIn event, serial 40, synthetic NO, window 0x5000001,
 mode NotifyUngrab, detail NotifyAncestor

KeymapNotify event, serial 40, synthetic NO, window 0x0,
 keys: 2 0 0 0 32 0 0 0 0 0 0 0 0 0 0 0
 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

KeyRelease event, serial 40, synthetic NO, window 0x5000001,
 root 0x13f, subw 0x0, time 27816259, (223,341), root:(223,365),
 state 0x4, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
 XLookupString gives 0 bytes:
 XFilterEvent returns: False