Failed to parse SourceMap with accounts-ui(-unstyled)

I was planning to tweak accounts-ui package a little bit, so I removed accounts-ui and added accounts-ui-unstyled separately. After this, I started getting this error in my console when I’m running my app which uses accounts-facebook, accounts-google, and accounts-twitter:

Failed to parse SourceMap:

The error persists even when if I checkout to my previous commit, or remove accounts-ui-unstyled and add accounts-ui.

The app works, but very slowly, and authentication takes years. I’m getting this error on Chrome, but even on Firefox, Still the authentication barely works.

Any help will be appreciated,