Lighthouse plugin recipe

Contents

package.json - declares the plugin's entry point (plugin.js)
plugin.js - instructs Lighthouse to run the plugin's own preload-as.js audit; describes the new category and its details for the report
audits/preload-as.js - the new audit to run in addition to Lighthouse's default audits

To run

Install lighthouse v5 or later.
Install the plugin as a (peer) dependency, parallel to lighthouse.
Run npx -p lighthouse lighthouse https://example.com --plugins=lighthouse-plugin-example --view

The input to --plugins will be loaded from node_modules/.

Result