importScripts ( '/node_modules/systemjs/dist/system.src.js' , '/node_modules/reflect-metadata/Reflect.js' , '/node_modules/zone.js/dist/zone.js' , './config.js' ) ; System . import ( './background_app.js' ) . then ( ( ) => console . log ( 'The application has started successfully' ) , error => console . error ( 'error loading background' , error ) ) ;