Japanese keyboard layout on Arch Linux KDE Plasma (or any Arch-based distro)
excuse the shit quality and bad cropping, I'm too lazy to properly learn Kdenlive ¯\_(ツ)_/¯
sudo pacman -Sy fcitx5-im fcitx5-mozc fcitx5-configtool adobe-source-han-sans-jp-fonts adobe-source-han-serif-jp-fonts noto-fonts-cjk
(if you get an error from this, it's likely because of the Adobe fonts, so just remove those and only install the Noto fonts)
sudo nano /etc/environment
GTK_IM_MODULE=fcitx
QT_IM_MODULE=fcitx
XMODIFIERS=@im=fcitx