Jekyll Custom Output Directory ("destination") Quirk In _config.yml

It appears that if you want to specify a custom output directory with Jekyll's destination: parameter, in its _config.yml file, this destination: line should be the first line.

In my personal experience, today, this caused the creation of both a custom output dir and Jekyll's default output dir _site:

url: foobar.com
destination: foobar/

Whereas this produced only the custom output dir:

destination: foobar/
url: foobar.com