At the moment it seems like we don’t have instructions on how to install VirtualBox on Debian. It is non-obvious, non-trivial, since you need kernel headers. Not that hard, though…
sudo apt-get update && sudo apt-get install linux-headers-$(uname -r) virtualboxWhere to add these instructions? Perhaps we should introduce a Windows logo button, a Linux / Debian logo button to support differencing instructions for those systems?
Or use Expand buttons? (Similar to the expand button used here https://www.whonix.org/wiki/Dev/Build_Documentation/9_full#64bit_Builds_.28Optional.29.)