If your build (or instant preview server) is failing due to the folowing error:
ERROR: YOUR SITE COULD NOT BE BUILT:
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Invalid date '<%= Time.now.strftime('%Y-%m-%d %H:%M:%S %z') %>': Document 'vendor/bundle/ruby/2.7.0/gems/jekyll-3.9.2/lib/site_template/_posts/0000-00-00-welcome-to-jekyll.markdown.erb' does not have a valid date in the YAML front matter.
Then you probably have not excluded the vendor directory from building. Because it is recommended to have all your gem installs in your local directory (which I wasn’t doing until Forestry) but Jekyll is going to try, and fail, to run negative test cases within itself.
So the solution is to exclude the vendor directory in your config file.
Where were we?
Yes, I now have a pretty neat CMS that I can access via web to make blog posts. I used said CMS for writing this blog post and can confirm it is pretty neat.