Basic configuration to minify and mangle produces completely broken JS

## Bug Report

The following command...

node_modules\.bin\babel _display.js _plan_ab.js _plan_en.js _p_cover.js _reco_sl.js _tdata.js _tid_dec.js _v_mm.js _v_name.js --no-comments >..\lib\nlpbndl3.js

...using a config as follows (babel.config.json)

{
"presets": [["minify", {
"mangle": {
"exclude": ["MyCustomError"]
},
"keepFnName": false
}]]
}

Produces a single JS file that appears "right".

However, Chrome can't load the JS file and just hangs.

I know this bug report is incomplete (as I can't upload all of my code), but wondering if anyone else has experienced this issue.