The CSS Jekyll plugin suite includes
html-proofer, a tool which scans
over the output of your website for broken links and issues with your HTML. You
can access HTML proofer directly by running bundle exec htmlproofer, but, we
recommend making use of the plugin version which will detect any errors at
build-time (the plugin is included in the
jeykyll-plugins-anu
gem which you’ve already got in your Gemfile if you’re using this theme).
It’s disabled by default; to enable this feature set the site.jekyll_proofer
variable to either warn or error. In error mode, if an issue is found with
your HTML Jekyll will terminate.
jekyll_proofer: error # or warn