I've selected Caps Lock as a switcher to another keyboard layout. After pressing Caps Lock in such apps as Konsole or Kate, the tray indicator switches to another layout, but the app doesn't react to the first key pressed after Caps Lock - no symbol is entered, Ctrl+C doesn't work etc. All subsequent characters are entered as they should. This problem doesn't happen in 'standard' fields, i.e. KDE Menu search, Keyboard testing field, Plasma Widget search etc. or non-KDE apps (Firefox). Reproducible: Always Steps to Reproduce: 1. Enable KDE layout switching, add the 2nd layout 2. Select "Switching to next layout" > "Caps Lock" 3. Press Caps Lock in Konsole or Kate Actual Results: Application doesn't react to the first key pressed after layout switching Expected Results: Applications should react to first key pressed after Caps Lock, not the second one. I'm using Konsole 3.0.1, KDE Frameworks 5.6.0, Kate 5.0.0.
This bug may be related to Qt bug https://bugreports.qt.io/browse/QTBUG-34068, which was probably fixed in Qt 5.4.1 (https://codereview.qt-project.org/#/c/102007/). Unfortunately, Arch Linux uses 5.4.0.
Confirming - very annoying. And unexpected :)
More strictly - at my case I haven't configured layouts via system settings, rather I have an appropriate options in xorg conf file /etc/X11/xorg.conf.d/10-evdev.conf: Option "XkbLayout" "us, ru" Option "XkbOptions" "grp:caps_toggle, grp_led:caps" But with kate/konsole I have the same issue - first-after-switch char is ignored. Additional small information: yes, kate and konsole are affected by the bug, but, say, yakuake (which, I guess, is based on the konsole) works as expected.
It seems that this bug was fixed in Qt 5.4.1. Both Kate and Konsole work fine now.
Thanks for reporting back.