The problem is that Uglify mangles too much by default in your case. As per bitcoinjs-lib instructions, you need to exclude certain names like this:
plugins: [
new webpack.optimize.UglifyJsPlugin({
mangle: {
except: [
'Array', 'BigInteger', 'Boolean', 'Buffer',
'ECPair', 'Function', 'Number', 'Point'
]
}
})
]
Use webpack instead of webpack -p after configuring the plugin.
It will work.