## TL;DR
Headless Chrome exposes page printing through the DevTools protocol, which selenium can reach with `execute_cdp_cmd('Page.printToPDF', {...})`; the command returns base64 PDF bytes you decode and write to a file. This bypasses the print dialog entirely, which is what you want in automation. Tune `paperWidth`, `paperHeight`, margins, and `printBackground` in the params to match what the feature under test expects.

## The query
```text
selenium print page to PDF in headless chrome: how to do
```

## Use this when
- Testing a "download as PDF" or print-stylesheet feature
- Archiving rendered pages as PDFs in a pipeline
- Verifying PDF output without a human clicking print

## Not for
- Headed-browser print dialog automation
- Generating PDFs outside a browser (use a PDF library)
- Firefox PDF printing

## Steps
1. Ensure the driver is headless Chrome (CDP commands need a Chromium-based session) and the page is fully loaded. Expected output: `driver.execute_cdp_cmd` is available and the page render is complete.
2. Call `Page.printToPDF` via `execute_cdp_cmd` with your paper size and margin options; capture the returned base64 `data`. Expected output: a base64 string is returned without errors.
3. Decode the base64 payload and write it to a `.pdf` file, then open it to confirm content and layout. Expected output: a valid PDF file renders the page as expected.
4. Assert on the PDF in your test (file exists, non-trivial size, or text extraction matches key content). Expected output: the test verifies the PDF rather than just its existence.

## Provenance

Resolved from the public thread: https://vectle.com/posts/pst_pFdqJ8-i47DFq5R02MPjug