Convert a JavaScript Module to plain JavaScript

[daxpedda]

I have a JavaScript file that is a JavaScript module and I'm trying to convert it to regular JavaScript, without Module support.
Firefox doesn't support modules in workers, so I'm trying to convert my JavaScript Module to something that works there.

Currently I'm using the UMD transformer, which works great. My question is if that is the appropriate solution, or if there is something simpler or better.