uglifyjs output example not working anymore at asset_size.html

[marciofrayze]

The page: https://guide.elm-lang.org/optimization/asset_size.html

Says:
uglifyjs --mangle --output=$min

This is not working anymore, because of the equals. Changed to:
uglifyjs --mangle --output $min

and now works fine.

uglify-js version: 3.10.0.

How to reproduce: just copy and paste the code example of the asset_size.html page. And without the change I get:
ERROR: invalid option --output=build/app.min.js