$ npm i -g html-differ@1.4.0
$ html-differ --help
/usr/local/lib/node_modules/html-differ/node_modules/coa/lib/cmd.js:243
UTIL.error(msg);
^
TypeError: UTIL.error is not a function
at process.<anonymous> (/usr/local/lib/node_modules/html-differ/node_modules/coa/lib/cmd.js:243:14)
at Object.onceWrapper (events.js:284:20)
at process.emit (events.js:196:13)