Eleventy: Set Nunjucks as the Default Markdown Template Engine
Despite using Nunjucks as my default templating language in Eleventy, for a long time, I was hesitant to just put markdownTemplateEngine: "njk" in my Eleventy configuration file, because I kept getting errors in the terminal about the nodes of my articles or blog posts did not exist, due to a conflict with the official Eleventy Navigation plugin.
Today I finally solved the issue by adding eleventyNavigation.key to my breadcrumb set up, so the Eleventy Navigation plugin would dynamically read my eleventyNavigation.key key for each post or article. Now I no longer have to individually add templateEngineOverride: njk, md in a post or article's frontmatter.