Thanks to @samliew, who find this cool news
There is new browser BLISK, ( https://blisk.io/) which comes with a nifty pre-installed set of popular devices in emulated mode that makes it easy for developers to test how their code renders across multiple devices and browsers. The feature is particularly useful for comparing how design responds to different screen resolutions and pixel ratios.
One major issue for me is that currently it is available only for Windows But authors promising Linux and Mac versions come soon... Well, will see
In fact, the OS X version is slated to arrive next month ( https://twitter.com/BliskBrowser/status/730520419325906944)
For now, all of you who has a Windows, could try it and tell us how it works with Webflow