As far as I know it's like writing a bash command:
// Windows"start":"start http://localhost:8081 & node bin/www"// Mac"start":"open http://localhost:8081 && node bin/www"// Linux"start":"xdg-open http://localhost:8081 && node bin/www"
For cross-platform support use open-cli.
Install it:
npm install --save-dev open-cli
Add it to your scripts:
"start": "open-cli http://localhost:8081 && node bin/www"
You just need to use start in the right order!
start
"start": "npm run dev & start http://localhost:8000",
Bad
"start": "start http://localhost:8000 & npm run dev",
Good