Common stealth issues

Viewport: Inner and outer width/height inconsistency

Problem:

If you you modify the viewport (e.g. page.setViewport({ width: 1920, height: 1080 })) you need to launch puppeteer with defaultViewport: null.

Example:

const browser = await puppeteer.launch({ defaultViewport: null })

Reason:

Puppeteer emulates viewport by default, so window resizing doesn't affect viewport.

Issue: #3688