Sounds like malware or a virus or possibly a bad add-on has installed itself in Firefox.
Nah, I doubt it. I get those from time to time too. Last time it happened, I posted a Hot Deal, and then immediately edited the title to fix a typo or something. BOOM! RECAPTCHA!
Expletive removed forum software...
Edit: Anyways, are you using a VPN? Possibly that same VPN IP is used by multiple users, and if it hasn't been outright IP-banned by the staff here, then the forums may appear to see multiple people from the same IP address logging in and posting, which could I guess trigger the recaptcha.
The other thing that I can think of, that might be causing issues, might be if pre-fetching is enabled in your Firefox options, causing repeated rapid page-load requests.
Please leave the profanity out of this forum.
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