What is Manjaro XFCE's default Input Method Framework and why do we have to rely on other packages (Fcitx, IBus) to add other keyboard layouts?

Based on IBus’ Arch Wiki page, ibus is integrated into the Gnome DE and I was wondering which Input Framework that xfce uses by default.

I’ve tried to add other layouts via the keyboard settings, but even though the languages (Chinese, etc.) are listed, they don’t seem to work. Why is that?

I got it to work using Fcitx5 and I don’t mind using Fcitx5, but I’m just curious why these features aren’t available for the default.

to set the keyboard layout is using setckbmap trough the xkb plugin

Having setxkbmap installed is not sufficient as requires also at least a IME(Input Method Editor) to enter languages that make use of Chinese characters. If you look inside /usr/share/X11/xkb/symbols and you read the cn file, you will see how it works, and how the symbos are “translated” to match the key codes from keyboard model and variant. Or you go by such keyboard:

Because are available for those that require them to install and configure. 90% (maybe more) of the people using Manjaro do not write in Chinese nor Japanese. You can always install manjaro-asian-input-support-fcitx or manjaro-asian-input-support-ibus if you need those.