Thanks for your answers.
Unfortunately in my game the perfomance loose is very big.
I'm using 1366x768 px and when game is played on 1920x1080 px monitor in fullscreen (on a laptop i5-2410M@2.3GHz, 4GB RAM, Intel HD Graphics 3000), framerate drops to 25FPS (from 60FPS).
Indeed additional launcher is a eventual possibility, but I'd like to make it look more professional and enable player change screen resolution (not scale game canvas) ingame.
Like I said I'm focusing on NW.js exporter.