Situation

Fails to use Fcitx input method in JetBrains IDEs on Linux to type certain characters, such as Chinese and Japanese.

Answer

• Ensure the Fcitx input method works in other GUI applications, such as Firefox, to confirm this is not an issue specific to JetBrains IDEs.

For X11 session

• Verify that you have set the following environment variables to enable Fcitx input method:

GTK_IM_MODULE=fcitx
QT_IM_MODULE=fcitx
XMODIFIERS=@im=fcitx

Example configuration: ~/.xprofile (used in X11 session)

export GTK_IM_MODULE=fcitx
export QT_IM_MODULE=fcitx
export XMODIFIERS=@im=fcitx

For Wayland session

Please check the official Fcitx documentation on how to configure it: https://fcitx-im.org/wiki/Using_Fcitx_5_on_Wayland

Notes

On Linux, any GUI applications started from the start menu or dock may use different environment variables than those started from the terminal. Please refer to this page https://wiki.archlinux.org/title/Environment_variables#Graphical_environment to ensure you have configured the necessary environment variables for the graphical environment. You will need to log out of your current user session or restart the computer to apply the newly configured environment variables.

To verify that the required Fcitx environment variables are correctly configured and can be used in IDE, open File | Settings | Tools | Terminal, click the Environment variables button, and check the list under the Include system environment variable section to ensure it includes variables like XMODIFIERS=@im=fcitx.