After updating from Kubuntu 22.04 to Kubuntu 24.04 blue language switcher appeared in tray (see screenshot). Looks like only white language swticher affects input language, switching blue language switcher has no effect.
Why second language switcher appeared and what I supposed to do with it?
You probably got fctix5 with the update. If you don’t need CJK (Chinese, Japanese, Korean) input methods you can uninstall it.
apt list --installed | grep fctix5 shows no packages
Interesting, do you have iBus installed?
Yes
$ apt list --installed | grep ibus
WARNING: apt does not have a stable CLI interface. Use with caution in scripts.
gir1.2-ibus-1.0/noble,now 1.5.29-2 amd64 [installed,automatic]
ibus-data/noble,noble,now 1.5.29-2 all [installed,automatic]
ibus-gtk3/noble,now 1.5.29-2 amd64 [installed,automatic]
ibus-gtk4/noble,now 1.5.29-2 amd64 [installed,automatic]
ibus-gtk/noble,now 1.5.29-2 amd64 [installed,automatic]
ibus/noble,now 1.5.29-2 amd64 [installed,automatic]
libibus-1.0-5/noble,now 1.5.29-2 amd64 [installed,automatic]
libibus-1.0-dev/noble,now 1.5.29-2 amd64 [installed]
libusb-1.0-0/noble,now 2:1.0.27-1 amd64 [installed,automatic]
libusbmuxd6/noble,now 2.0.2-4build3 amd64 [installed,automatic]
python3-ibus-1.0/noble,noble,now 1.5.29-2 all [installed,automatic]
But I don’t remember installing it.
I think blue color means it’s ibus, not fcitx. fcitx5 has white color.
@Koolberg Distros may install either by default to support languages that cannot be typed with just a keyboard, primarily for Chinese/Japanese/Korean. They may want their default install to support as many languages as they can. In case of fcitx5 that’s currently a bad idea as it interferes with Plasma’s keyboard layout switching.
(It’s great software though, I’ve had good experiences typing Japanese with fcitx5 while ibus was rather slow and didn’t feel as good. But if you don’t need it and don’t plan to use it, it’s rather invasive).
Both ibus and fcitx5 really want to handle language switching completely; fcitx5 is currently a bit more aggressive about it. To be able to use them, you should setup your keyboards/languages in the ibus or fcitx5 configuration; they’re not really compatible with the Plasma keyboard configuration. If you don’t need their advanced capabilities, you can just get rid of them without negative consequences.
Problem solved.
It turns out new version of zoom requires iBus even if you are already using another language switcher.
$ aptitude why ibus
i zoom Depends ibus
You can disable ibus in the Virtual Keyboard section of System Settings – input methods like fcitx5 and ibus count as virtual keyboards. Just set it to none. That should hide the switcher from the panel, and make sure it doesn’t interfere with your regular keyboard layout settings.
You could also hide it from the system tray by setting it to “Always hidden” in the system tray settings if that doesn’t work, but that could still cause conflicts between Plasma’s keyboard layout switching and the input method’s language switching.