Networking Completely Failed

["Harley A.W. Lorenzo" <hl1998@protonmail.com>]

On a Debian testing laptop that I switched from Cinnamon to XFCE4 (without xfce4-goodies initially) rebooting into the new desktop environment caused all my network interfaces except from loopback to fail. The network manager doesn't appear, Ethernet does not work, restarting any of the system services related to networking doesn't work (and interestingly systemd-networkd was disabled at first but renabling has not caused anything different to happen.)

Although reinstalling is an option to fix this, I would like to learn how to fix this myself as something in the network ecology has definitely failed. Thank you all in advance.

I