Fonts

The Arch Wiki provides some fonts to use for Japanese localisation.

sudo pacman -S adobe-source-han-sans-jp-fonts adobe-source-han-serif-jp-fonts noto-fonts-cjk otf-ipaexfont ttf-hanazono

Fcitx and Mozc

My preferred IMF/IME is Fcitx and Mozc.

Install the following packages:

sudo pacman -S fcitx5-im fcitx5-lua fcitx5-mozc

And now for some manual configuration. Within the KDE system settings, under keyboard, change:

  1. Your keyboard layout to Japanese

  2. Keyboard model to Generic | Japanese 106-key

  3. Virtual keyboard to “Fcitx 5”

Then under input method:

  1. Input method (off) to Keyboard - Japanese

  2. Input method on to Mozc

Then configure mozc to use kana input instead of romaji.

Lastly create the following file:

~/.config/fcitx5/conf/mozc.conf

# Initial Mode
InitialMode=Hiragana
# Vertical candidate list
Vertical=True
# Expand Usage (Requires vertical candidate list)
ExpandMode="On Focus"
# Fix embedded preedit cursor at the beginning of the preedit
PreeditCursorPositionAtBeginning=False
# Hotkey to expand usage
ExpandKey=Control+Alt+H