From Fedora Project Wiki
There are various ways to input emoji (emoticons) in applications.
GNOME
Gtk 3 and 4 applications support Emoji input via Ctrl+Period (Ctrl-.).
In almost any application (eg browsers) you can also use ibus Emoji input:
- To activate ibus Emoji mode:
- in Fedora 37 and later press Super+Space
- in Fedora 36 and earlier press Ctrl+Period (Ctrl-.)
- Then an "e" prompt appears.
- Either enter a keyword in pre-edit and then space to see candidates
- or press Space to bring up the Emoji selector.
Note that the ibus emoji input is not available in Live images (see bug).
KDE
Qt supports Emoji input via Super+Period (Win-.).
LibreOffice
Sometimes monochrome emoji are preferred to colored emoji.