If you install a new version of MX that is using the same Debian base there is an application, aptik-gtk (Package Installer > MX Test Repo) that can bring in your applications and application configurations plus much more from your previous install. (It can also be used between Debian bases, though you should be more careful about what you preserve). This saves considerable time in setting up your new system.
You run aptik on your current install and pick Backup for those items you want to migrate. Directories and files are created containing the pertinent applications and configurations. These directories and files should be saved to a location that will not get overwritten by the new install such as a data partition or external drive. Then on your new install you execute Restore to install those apps.
- Panel configurations are not fully restored.
- Some appearance items are not restored depending on what you have set up in your old install.
- Hidden configuration files in the Home folder may not be restored. It is recommended you save them prior to a new install to a location you can retrieve from later.
- Items in Session and Startup > Application Autostart that you added will not be restored and have to be re-entered. You can also try saving the file ~/.config/autostart/ and reusing it after the upgrade.