Seeing 404 URL on hints when bootstrapping LXD

not sure where this should be reported, but I just happened to be reinstalling Juju on LXD… and saw a link hinting it can help me run better… but when I click it I got 404’d

https://github.com/lxc/lxd/blob/master/doc/production-setup.md
 juju bootstrap localhost
Since Juju 2 is being run for the first time, it has downloaded the latest public cloud information.
Creating Juju controller "localhost-localhost" on localhost/localhost
Looking for packaged Juju agent version 2.9.35 for amd64
Located Juju agent version 2.9.35-ubuntu-amd64 at https://streams.canonical.com/juju/tools/agent/2.9.35/juju-2.9.35-linux-amd64.tgz
To configure your system to better support LXD containers, please see: https://github.com/lxc/lxd/blob/master/doc/production-setup.md
Launching controller instance(s) on localhost/localhost...
 - juju-8ac444-0 (arch=amd64)                 
Installing Juju agent on bootstrap instance
Fetching Juju Dashboard 0.8.1
Waiting for address
Attempting to connect to 1.2.3.4:22
Connected to 1.2.3.4
Running machine configuration script...
Bootstrap agent now started
Contacting Juju controller at 1.2.3.4 to verify accessibility...

Bootstrap complete, controller "localhost-localhost" is now available
Controller machines are in the "controller" model
Initial model "default" added