Posting for people that are looking for a solution that works with NW.js (ancient versions used the name Node-Webkit). First things first, this Chromium Arg is outdated and got deprecated quite a while ago so it's completely useless now.
Currently the only workaround (AFAIK) is to do the following:
Steps to open multiple NW.js windows:
- Add the Browser and Keyboard (optional) plugins
- Add the condition on button pressed
- Add the execute javascript action and execute this code: "window.open('" & Browser.URL & "');"
- Open as many windows as you like by pressing the selected button
Warning: Don't do the following things:
- Execute on start of the layout
- Open a new window using the browser action open new window
- Execute JS code while the 1st instance of your project still loads (e.g. loader layout)