If you point the installer to an invalid YAML file, it doesn't abort immediately with a user-friendly error, but instead runs for quite a long time, producing multiple errors like:
[InvalidArgumentException]
Unable to parse line 6 (<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN").
If you point the installer to an invalid YAML file, it doesn't abort immediately with a user-friendly error, but instead runs for quite a long time, producing multiple errors like: