Subdomains not working in 1.0.0

Created by: anomaly44

Description

Since 1.0.0 we cannot visit subdomains on the dev server anymore. This is usfeful for devs who use subdomains to serve different data based on subdomains with CRA.

Expected behavior

Visiting the app on http://test.localhost:3000/ should display the app the same as the usual: http://localhost:3000/

Actual behavior

Instead of the app we get: Invalid Host header

Reproducible Demo

create a new react app and visit any subdomain.

Extra

• Would it be possible to add an option to the package json to use disableHostCheck: true in the webpackDevServer.config ?
• is it possible to add an option to open the browser on a subdomain?