Undefined is not a function in readable-stream this.once

Hey! I'm not sure if this bug belongs here, but if I do:

npm i browserify browserify-fs through2 beefy --save

and have a file like test.js:

var fs = require('browserify-fs')
var through = require('through2')
var t = through()

When I run beefy or testling I get in any readable-stream module the error:

Uncaught TypeError: undefined is not a function in _stream_duplex.js at line 71:
this.once('end', onend);

This error doesn't occur If I don't use browserify-fs or if I use and old version of browserify like 3.6.41.

My versions in package.json are:

  "dependencies": {
    "beefy": "^2.1.0",
    "browserify": "^5.10.0",
    "browserify-fs": "^1.0.0",
    "through2": "^0.6.1"
  }

Start with the reported test.js dependency setup and reproduce the failure using beefy or testling. Inspect readable-stream/_stream_duplex.js at line 71 and compare behavior with browserify 3.6.41; done means the example runs without the undefined-function error when using the reported dependency versions.