From terminal from root of app, run the deployment script
npm run build:linux
It creates a cache and a build folder. cache is a folder used by deploy to keep the latest version needed to build and package the app, to avoid having to re-download it every time. While the packaged app ready for use can be found in the build folder.
It packages the app as a AppImages that works across linux distribution see deployment section and this issue and corresponding PR for more details.