Hi Feike,I also meet this problem recently. I can use the Uglify to
compress my Js file, it will fails when I try to use YUI compressor.The
file I want to compressed invoke React, And I already use babel to
translate it to ES5 synax.As you know the YUI Compressor is already
stopping upgrades long time ago, maybe it not supports the new tech.Is
there any solution I can replace YUI on AEM?