docs: Add note about creating a non-root user.

Tweaked by tabbott to move most of the content into the remote
development documentation, both for brevity in the main docs as well
as clarity.

Fixes #10694.

docs/development/remote.md

@@ -30,6 +30,23 @@ If you have poor internet connectivity, we recommend using
 [Mosh](https://mosh.org/) as it is more reliable over slow or unreliable
 networks.
 
+## Setting up user accounts
+
+You will need a non-root user account with sudo privileges to setup
+the Zulip development environment.  If you have one already, continue
+to the next section.
+
+You can create a new user with sudo privileges by running the
+following commands as root:
+* You can create a `zulipdev` user by running the command `adduser
+zulipdev`. Run through the prompts to assign a password and user
+information.  (You can pick any username you like for this user
+account.)
+* You can add the user to the sudo group by running the command
+`usermod -aG sudo zulipdev`.
+* Finally, you can switch to the user by running the command `su -
+zulipdev` (or just login to that user using `ssh`).
+
 ## Setting up the development environment
 
 After you have connected to your remote server, you need to install the

docs/development/setup-advanced.md

@@ -17,6 +17,11 @@ that's running one of:
 
 You can just run the Zulip provision script on your machine.
 
+**Note**: you should not use the `root` user to run the installation.
+If you are using a [remote server](../development/remote.html), see
+the
+[section on creating appropriate user accounts](../development/remote.html#setting-up-user-accounts).
+
 **Warning**: there is no supported uninstallation process with this
 method.  If you want that, use the Vagrant environment, where you can
 just do `vagrant destroy` to clean up the development environment.