Extension: User-Agent Switcher and Manager
Browser: Mozilla Firefox
Target Site: https://www.lampandlight.co.uk/customer/account/login/
Issue Description:
When the extension is active in Firefox, attempting to submit forms protected by Google reCAPTCHA v3 (using Alpine.js) fails with a client-side JavaScript crash:
TypeError: can't access property "then", Y.A is null
executeGrecaptcha (login:4616)
recaptcha__en.js:1640
submitForm (login:4642)
Root Cause & Observations:
- Override of navigator properties causes Google's reCAPTCHA initialisation object (
Y.A) to evaluate as null, causing .then() calls to throw a TypeError during form post.
- Adding the domain or
gstatic.com to Black-List Mode does not prevent this failure, indicating content scripts or navigator property overrides execute before domain exclusion checks resolve.
Expected Behaviour:
Blacklisting a domain should completely bypass user-agent modifications and script injections so reCAPTCHA can execute its handshake cleanly.
Extension: User-Agent Switcher and Manager
Browser: Mozilla Firefox
Target Site: https://www.lampandlight.co.uk/customer/account/login/
Issue Description:
When the extension is active in Firefox, attempting to submit forms protected by Google reCAPTCHA v3 (using Alpine.js) fails with a client-side JavaScript crash:
TypeError: can't access property "then", Y.A is null
executeGrecaptcha (login:4616)
recaptcha__en.js:1640
submitForm (login:4642)
Root Cause & Observations:
Y.A) to evaluate as null, causing.then()calls to throw a TypeError during form post.gstatic.comto Black-List Mode does not prevent this failure, indicating content scripts or navigator property overrides execute before domain exclusion checks resolve.Expected Behaviour:
Blacklisting a domain should completely bypass user-agent modifications and script injections so reCAPTCHA can execute its handshake cleanly.