NxtChg

This is a library of diverse stand-alone components, some are in PHP and C++. I don't think it's suitable for NPM.

These components are not Node.JS modules, so I see no reason to use NPM for them.

Are you using vue-cli?

This component is for pure browser setup: you load vue.js and you load vs-notify after it. If you use anything fancy, you need to read how to register Vue components...

I don't use vue-cli and so I have no idea :)