New answers tagged validation
This kind of spam prevention is usually provided by the reCAPTCHA service from Google. IMHO this is an advanced spam protection service based on the principles of CAPTCHA. While I do not think reCAPTCHA is a technical name and there could also be other advanced implementations of CAPTCHA-like spam protection.
Try Screaming Frog - it can crawl hashbang-ed urls: http://www.deepcrawl.com and http://www.crawlajax.com promise to be able to it too.
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