Useful links are:

• ArchWiki: Dell XPS 13 (9360)
• ArchWiki: DisplayLink
• Average Linux User: 20 Things to do After Installing MX Linux (2021)

The installation was smooth. My additional steps were:

1. add boot parameter pci=noaer to get rid of AER (Advanced Error Reporting) errors in kernel ring buffer (dmesg);
2. add boot parameter intel_iommu=igfx_off as workaround for problems with Qualcomm ath10k_pci WLAN chipset (and get rid of DMA errors in kernel ring buffer);
3. add this line to /etc/apt/sources.list.d/debian-stable-updates.list, else some dev packages like libgtk-3-dev are not available in package manager;

   deb-src http://deb.debian.org/debian/ bullseye-updates non-free contrib main

4. set-up DisplayLink software (to use my D3100 docking station) as described at DisplayLink Knowledge Base:
   • configure MX boot using systemd, may be persistent via MX Tools (DisplayLink requires systemd on D-Bus);
   • download DisplayLink driver software from download page;
   • download latest evdi driver tarball from GitHub, especially when using a 6.x Linux kernel;
   • extract DisplayLink according to article Porting the DisplayLink Ubuntu driver to other Linux distributions;

     ./displaylink-driver-x.x.xx.run --noexec --keep --target driver

   • in subdirectory driver replace evdi.tar.gz by the downloaded (latest) version of evdi
   • change to subdirectory driver and install DisplayLink;

     SYSTEMINITDAEMON=systemd ./displaylink-installer.sh

   • activate 2nd monitor:

     xrandr --setprovideroutputsource 4 0

     putting the command into /etc/X11/Xsession.d/96rho_init_xrandr;

lsusb -d 17e9: # vendor ID of DisplayLink devices
systemctl status displaylink-driver.service
systemctl restart displaylink-driver.service
xrandr --listproviders
xrandr --current