Actually looks like the build is failing …
.md file is here
Jekyll build7s
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Theme: jekyll/minima
Theme source: /tmp/jekyll-remote-theme-20200308-1-1oztv15
Remote Theme: Using theme jekyll/minima
EntryFilter: excluded /docker-compose.yml
EntryFilter: excluded /Makefile
EntryFilter: excluded /Gemfile
EntryFilter: excluded /Gemfile.lock
EntryFilter: excluded /action.yml
Reading: _posts/2020-01-14-test-markdown-post.md
Reading: _posts/2020-03-06-fastpages-actions.md
Reading: _posts/2020-02-20-test.md
Reading: _posts/2020-02-21-introducing-fastpages.md
Jekyll Feed: Generating feed for posts
Generating: JekyllFeed::Generator finished in 0.000617701 seconds.
Generating: JekyllRelativeLinks::Generator finished in 0.0003523 seconds.
Rendering: _posts/2020-01-14-test-markdown-post.md
Pre-Render Hooks: _posts/2020-01-14-test-markdown-post.md
Rendering Liquid: _posts/2020-01-14-test-markdown-post.md
Rendering Markup: _posts/2020-01-14-test-markdown-post.md
Requiring: kramdown-math-katex
Rendering Layout: _posts/2020-01-14-test-markdown-post.md
Layout source: site
Liquid Exception: no implicit conversion of nil into String in /_layouts/default.html
Remote Theme: Cleaning up /tmp/jekyll-remote-theme-20200308-1-mck3gj
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Jekyll 4.0.0 Please append `--trace` to the `build` command
for any additional information or backtrace.
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