It seems this doesn't work properly on experimental: ckeditor won't load and the console logs:

Error: [CKEDITOR.resourceManager.load] Resource name "lineheight" was not found at "/ckeditor-plugins/lineheight/plugin.js?t=H0CF"

This is probalbly related to a concern @Klaas Andries de Graaf expressed at some point, whether the use of the 'napa' dev dependency in package.json would interfere with build and deploying.

About the napa package: it is a dev only package that is used during 'npm install' phase that helps use a regular (non-npm packaged) git repo as an npm package. I used that in order to use the lineheight plugin directly from the source git repo ( https://github.com/lotusgodkk/lineheight ).

I assume the reason it is not working is some failure during 'npm install' ( which I assume is part of regular deployment process ), and for some reason the relevant git repo is not locally cloned. Or the napa package is not properly installed?

I tested the current package.json locally by removing the node_modules/ directory and running npm install and it works fine. I am not sure how else to test the build/deploy process.