Xorg.wrap error message on fresh install of stretch

[orrp]

Please describe your issue:

After installing stretch with -t xiwi, attempting to run sudo startxiwi xterm returned the following message:
Xorg.wrap: Only console users are allowed to run the X server.

If known, describe the steps to reproduce the issue:

Install stretch with -t xiwi

Resolution

In order to resolve the issue, I followed step 1 here, namely

edit /etc/X11/Xwrapper.config to include the line:
allowed_users=anybody