single instance

src/background.ts

@@ -16,7 +16,10 @@ import { logger } from './main/logger'
 import os from 'os'
 const isDevelopment = process.env.NODE_ENV !== 'production'
 
-// Scheme must be registered before the app is ready
+if (!app.requestSingleInstanceLock()) {
+  app.exit()
+}
+
 protocol.registerSchemesAsPrivileged([{ scheme: 'app', privileges: { secure: true, standard: true } }])
 app.allowRendererProcessReuse = true
 if (!config.get('hardwareAcceleration')) {