src/main.ts

@@ -24,6 +24,8 @@ app.on('window-all-closed', () => {
   }
 });
 
+app.on('before-quit', disconnect);
+
 app.on('activate', () => {
   // On OS X it's common to re-create a window in the app when the
   // dock icon is clicked and there are no other windows open.