Since the dig function used in /lib/jekyll/tidy.rb was introduced in Ruby 2.3, support for older Ruby versions is broken and produces the following error message
path/to/ruby/2.2.0/gems/jekyll-tidy-0.2.0/lib/jekyll/tidy.rb:35:in `ignore_env?': undefined method `dig' for #<Jekyll::Configuration:0x000000024e3750> (NoMethodError)
Since the
dig
function used in/lib/jekyll/tidy.rb
was introduced in Ruby 2.3, support for older Ruby versions is broken and produces the following error message