IME not supported on linux (again)

[scarf005]

fun, #1497 happens again after 2 years. this time korean cannot be written at all. reproducible since 0.3 and latest commit.

output of im-config:

Current configuration for the input method:
 * Default mode defined in /etc/default/im-config: 'auto'
 * Active configuration: 'ibus' (normally missing)
 * Normal automatic choice: 'ibus' (normally ibus or fcitx5)
 * Override rule: 'zh_CN,fcitx5:zh_TW,fcitx5:zh_HK,fcitx5:zh_SG,fcitx5'
 * Current override choice: '' (Locale='ko_KR')
 * Current automatic choice: 'ibus'
 * Number of valid choices: 3 (normally 1)
 * Desktop environment: 'KDE'
The configuration set by im-config is activated by re-starting the system.
Explicit selection is not required to enable the automatic configuration if the active one is default/auto/cjkv/missing.
  Available input methods: ibus fcitx5 kime xim
Unless you really need them all, please make sure to install only one input method tool.