Pinning npm dependencies resulting in duplicated code in a build

index.js

var woofmark = require('woofmark');
var dragula = require('dragula');

package.json

{
  "name": "dep-test",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    "dragula": "^3.5.1",
    "woofmark": "^4.0.2"
  }
}

result.txt

> browserify index.js | grep 'function addEventEasy (el, type, fn, capturing) {'
function addEventEasy (el, type, fn, capturing) {
function addEventEasy (el, type, fn, capturing) {

# addEventEasy comes from crossvent which is a dependency of both dragular and woofmark
# but pinned at different patch versions, which result in full crossvent module duplication