The following script (or cli) will reduce MXLinux 18 to a relatively small distro.

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#!/bin/bash
sudo apt update
sudo apt-get remove –purge aisleriot asunder chromium-bsu chromium-bsu-data clementine clipit dconf-editor dict fbreader featherpad feh firefox galculator geany geany-common gimp gimp-data gmtp gnome-hearts gnome-mahjongg gnome-ppp gnome-schedule gscan2pdf gsmartcontrol gtkhash gtkhash-common guvcview* hexchat htop lbreakout2 lbreakout2-data libreoffice* lightning luckybackup luckybackup-data mc mc-data nomacs nomacs-l10n onboard onboard-common onboard-data orage pdfshuffler peg-e pppoeconf qpdfview* samba samba-common samba-common-bin samba-libs simple-scan smtube swell-foop thunar-gtkhash thunderbird vlc xfce4-notes xfce4-notes-plugin xfce4-sensors-plugin xfce4-taskmanager xfce4-dict
#

The following terminal commands will clean things up after the previous deletion(s).
sudo apt autoclean && sudo apt autoremove –purge
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If you wish to remove xfce : 

cut & paste the following into a terminal:
sudo apt remove xfdesktop4 xfce4-* libxfce4-*