flip to headless mode by default

src/logic.js

@@ -246,7 +246,7 @@ const map_event = ({ node: event }) => {
 
 const open_browser = async () => {
   const browser = await puppeteer.launch({
-    headless: false,
+    headless: true,
     args: ['--disable-dev-shm-usage'],
   });
   return browser;