[REGRESSION]: Google captcha appears on 1.61.1, works fine on 1.60.0

[SakalOFF]

Checklist before reporting

• I have searched for similar issues and didn't find a duplicate.
• I have updated to the latest version of Patchright to verify the regression still exists.
• I have verified that this regression does not occur when using Playwright directly.

GOOD Patchright Version

1.60.0

BAD Patchright Version

1.61.1

Operating System

Windows 10

Reproduction (self-contained)

import asyncio
from patchright.async_api import async_playwright

async def main():
    async with async_playwright() as p:
        context = await p.chromium.launch_persistent_context(
            user_data_dir="./userdir",
            headless=False,
            channel="chrome",
        )
        page = await context.new_page()
        await page.goto("https://www.google.com")
        # No automation — just wait for manual input
        await asyncio.sleep(180)  # manually type something and press Enter
        await context.close()

asyncio.run(main())

Expected Behavior

Search results page loads normally without any captcha (as in 1.60.0)

Actual Behavior

After manually typing a search query and pressing Enter (no automation involved),
Google shows a captcha challenge when using patchright==1.61.1.
This strongly suggests that the browser fingerprint itself is being detected,
not the automation of keystrokes.
Downgrading to patchright==1.60.0 resolves the issue immediately

[SakalOFF]

Additional findings:

The issue appears to be environment-specific rather than version-specific.

• patchright==1.56.0 on Laptop (Windows 10): NO captcha
• patchright==1.56.0 on Desktop PC (Windows 11): captcha appears even with manual input

This suggests the root cause may be related to browser fingerprinting differences
between machines (hardware fingerprint, screen resolution, GPU, fonts, etc.)
rather than patchright version alone.

Both machines are on the same local network, same Chrome version, same patchright version.
Manual input (no automation) still triggers captcha on the Desktop PC —
meaning the issue is in how the browser presents itself to Google, not in automation detection.

[SakalOFF]

Update:

Tested patchright==1.60.0: captcha behavior is unpredictable —
sometimes appears, sometimes does not, even under identical conditions.
patchright==1.56.0 remains the only consistently working version (consistent only on one specific machine — behaves differently on other hardware).

Note: We were unable to find reliable reproduction steps.
The captcha seems to be triggered by browser fingerprint differences
between machines rather than automation detection, since it appears
even with fully manual input on some hardware.

Leaving this open in case others can narrow it down further.

[SakalOFF]

Update:

Tested patchright 1.56.0 and 1.60.0 — no captcha on both machines (Dell i5 7200U laptop and Xeon 2680v4 X99 desktop). Works consistently.

Root cause identified: locale="en-US" parameter in launch_persistent_context caused a detectable mismatch between the main thread and Web Workers on Russian-language Windows. Workers inherit the system locale (ru-RU) while the main thread reports en-US, which Google flags as a bot signal. Removing locale="en-US" resolved the issue on both machines.

Version summary:

1.56.0 and 1.60.0 — works consistently on both machines ✅
1.61.1 — captcha triggered, not usable

[Vinyzu]

I couldnt reproduce this Regression.
For me on 1.56.0, 1.60.0 and 1.61.1 i always get a clean pass without a locale and the same block with a locale.
Note that passing a locale isnt easily achievable stealthy because of WebWorker leaks.

If you find a clean Regression Repro that i can validate, please open a new issue! (Closing this as invalid for now as its a bit cluttered).

[mermyly]

possibly due #117

[Vinyzu]

Upgrade to 1.61.2