Missing pipes in Installation Guide

[ReGuess]

For the following set commands in step 6 of the instructions for Ubuntu on the Installation Guide:

echo 'ADD_EXTRA_GROUPS=1'
sudo tee -a /etc/adduser.conf

echo 'EXTRA_GROUPS=video'
sudo tee -a /etc/adduser.conf

Each pair should be linked by a pipe; otherwise, the output of echo gets printed directly to stdout, and tee, lacking a piped input, waits there listening on stdin.