Hey everyone! I’m working on a project with Puppeteer and I’ve hit a bit of a snag. I’ve got a headless browser instance running, but now I need to switch it to non-headless mode without losing my place. Is this even possible?
I tried simply changing the headless option to false while the browser was running, but it didn’t seem to do anything. Has anyone successfully done this before? If so, what’s the trick?
I’m really hoping there’s a way to do this without having to start a whole new browser session. It would save me a ton of time and hassle if I could just flip a switch and see what’s going on in the browser.
Any tips or code examples would be super helpful. Thanks in advance for any advice you can give!
Unfortunately, there’s no direct way to convert a headless Puppeteer instance to non-headless mid-session. Puppeteer’s architecture doesn’t support this kind of runtime switch. The headless mode is set when launching the browser and can’t be changed dynamically.
However, you might consider a workaround. You could run two browser instances simultaneously - one headless and one non-headless. When you need to visualize, you can transfer the state (cookies, localStorage, etc.) from the headless instance to the non-headless one. This approach isn’t perfect and might be resource-intensive, but it could serve your purpose.
Alternatively, you could use a remote debugging port to connect to the headless browser with Chrome DevTools. This allows you to inspect the page without actually making it non-headless. It’s not exactly what you asked for, but it might help you debug your script effectively.
hey sam, swicthing mid-session headless to non-headless isnt possible in puppeteer. headless mode is fixed at launch. you could try running both instances concurrently and syncing state, but its clunky.
I’ve faced a similar challenge in my projects. While it’s not possible to switch from headless to non-headless mid-session, I’ve found a workaround that might help. Instead of trying to convert the session, I create a non-headless browser instance right from the start, but keep it minimized. This way, when I need to visualize what’s happening, I can simply bring that window to the foreground.
To minimize resource usage, I set a lower resolution for this window. It’s not perfect, but it’s saved me countless hours of debugging. Another trick I’ve used is leveraging the page.screenshot() function strategically to get visual feedback without the overhead of a full GUI.