--fingerprint dropped deviceScaleFactor, so the identity contradicted itself - #26
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… itself `playwright_context_kwargs` mapped the user agent, the locale, the timezone and the screen onto the browser context and ignored `deviceScaleFactor`, which the fingerprint API returns beside them. Measured 2026-09-11 against the live API and a live browser: a fingerprint stating `deviceScaleFactor: 1.25` produced a browser reporting `window.devicePixelRatio === 1`. That is the mismatch this flag exists to prevent, on an axis any fingerprinter reads for free and for nothing: the paid identity said one thing and the browser said another, on every run, silently. Same shape as the three defects the family notes already record for this file -- a key the API returns that nothing applies -- and found the same way, by comparing a live browser against the fingerprint instead of by reading the code. Playwright takes it as its own context option, so the fix is to pass it. Verified in a live browser with this repo's own client: 1.25 requested, 1.25 reported, with the user agent, timezone and locale still matching. The check is pinned in the offline suite so it stays fixed. Found while auditing a new sibling repo against the family notes. All five repos in this family had it. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Code reviewNo issues found. Checked for bugs and CLAUDE.md compliance. |
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playwright_context_kwargsmapped the user agent, the locale, the timezone andthe screen onto the browser context and ignored
deviceScaleFactor, whichthe fingerprint API returns beside them.
Measured 2026-09-11 against the live API and a live browser:
nl-NLEurope/AmsterdamThat is the mismatch this flag exists to prevent, on an axis any
fingerprinter reads for free and for nothing: the paid identity said one
thing and the browser said another, on every run, silently.
Same shape as the three defects the family notes already record for this
file — a key the API returns that nothing applies — and found the same way:
by comparing a live browser against the fingerprint instead of by reading
the code.
Playwright takes it as its own context option, so the fix is to pass it.
Verified in a live browser with this repo's own client: 1.25 requested,
1.25 reported, with the user agent, timezone and locale still matching. The
check is pinned in the offline suite so it stays fixed.
Found while auditing a new sibling repo (
catawiki-scraper) against thefamily notes. All five repos in this family had it; this is the same
patch in each.
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