Edite o arquivo .config / user-dirs.dirs colando-o em um terminal:
gedit ~/.config/user-dirs.dirs
Você verá um texto assim:
# This file is written by xdg-user-dirs-update
# If you want to change or add directories, just edit the line you're
# interested in. All local changes will be retained on the next run
# Format is XDG_xxx_DIR="$HOME/yyy", where yyy is a shell-escaped
# homedir-relative path, or XDG_xxx_DIR="/yyy", where /yyy is an
# absolute path. No other format is supported.
#
XDG_DOWNLOAD_DIR="/data/downloads"
XDG_TEMPLATES_DIR="$HOME/Templates"
XDG_PUBLICSHARE_DIR="$HOME/"
XDG_DOCUMENTS_DIR="/data/drive"
XDG_MUSIC_DIR="/data/music"
XDG_PICTURES_DIR="/data/pictures"
XDG_VIDEOS_DIR="/data/videos"
XDG_DESKTOP_DIR="/data/desktop"
A entrada XDG_DESKTOP_DIR=
deve ser igual à sua pasta da área de trabalho (provavelmente "$ HOME / Desktop"). Se estiver faltando, apenas digite-o e salve o arquivo. Reinicie e deve estar de volta.