I changed entry point as below.

entry: { 'main': './ClientApp/boot.ts',
'logincallback': './ClientApp/scripts/login/callback.ts'
},

Here I have added one more entry point called 'logincallback'. and it gives

Uncaught ReferenceError: vendor_'00BLABLA000' is not defined.

Someone else had faced this as well. See below.

#717