Using a spell-checker in gajim

• What you need

gtkspell, aspell and aspell-LANG where LANG is the one or more language(s) you want : en, fr, etc...

• Use and change spell language for whole gajim

In ACE, search for spell, active speller and write the default language two letters code.

• Use and change spell language per contact/group chat

Open a chat, right click where you usually write (red arrow on picture), and choose in spelling language submenu.