Reconsider whether it's safe to rely on recent Uglify versions

[gaearon]

I don't have all the context but just flagging to look at this before cutting 2.x.

https://mobile.twitter.com/AdamRackis/status/987346564527116288
react/react#12555 (comment)
react/react#12434

[Timer]

Unfortunately, babel-minify is really slow: neutrinojs/neutrino#809 (comment).

[gaearon]

I’d be cautious with that too because we couldn’t get it to work reliably enough at FB about a year ago.

[eliperelman]

Other than build times, babel minify hasn't been too bad. I have been bit before by variable name mangling though, which was painful to debug. We are in a tough period right now with both Uglify and Babel minify not receiving the maintenance love they probably need.

[Timer]

We've switched to Terser.