Ramping up our conversion to Lucee, I see that cfdocument is not retrieving the external css document into the created PDF. Is there a best practice to apply an external css document to html that sits within a cfdocument tag? (can move to cfml-general if in wrong channel)

Do CSS styles inline. The PDF engine in Lucee doesn't render the same way.

right - you could retrieve the contents of the css file and place inline with the <cfdocument> content

you might need to use a fully qualified url for external resources like css or images

These are all great suggestions and I will look into each. I am so excited to see our codebase move to Lucee and to be part of this group. Thanks for your answers!