webtorrent-desktop: `npm start` does not start on Debian Node v11

npm start on master does not produce any UI and gives me an error.

What version of WebTorrent Desktop? (See the ‘About WebTorrent’ menu)

• master

What operating system and version? Debian Stretch $ node -v v11.6.0

What did you do? npm start

What actually happened?

$ npm start

> webtorrent-desktop@0.20.0 start /home/james/opt/webtorrent-desktop
> npm run build && electron .


> webtorrent-desktop@0.20.0 build /home/james/opt/webtorrent-desktop
> buble src --output build

Missing config file: Creating new one
A JavaScript error occurred in the main process
Uncaught Exception:
/home/james/opt/webtorrent-desktop/node_modules/cp-file/index.js:60
		...options
		^^^

SyntaxError: Unexpected token ...
    at createScript (vm.js:74:10)
    at Object.runInThisContext (vm.js:116:10)
    at Module._compile (module.js:533:28)
    at Object.Module._extensions..js (module.js:580:10)
    at Module.load (module.js:503:32)
    at tryModuleLoad (module.js:466:12)
    at Function.Module._load (module.js:458:3)
    at Module.require (module.js:513:17)
    at require (internal/module.js:11:18)
    at setupStateSaved (/home/james/opt/webtorrent-desktop/build/renderer/lib/state.js:114:16)

Node kept running but the UI did not show up.

Maybe package.json needs some babel-polyfill?