The t3versions bot is a friendly web crawler, which analyzes the TYPO3 major version of a website. You can identify the bot by the user agent string:
Mozilla/5.0 (compatible; t3versionsCheckBot/1.2; +https://www.t3versions.com/check-bot)
The t3versions bot will save the TYPO3 version number and several public available data about the identified TYPO3 website to a database. Collected data is aggregated for statistical purposes only and publicly available at https://www.t3versions.com/statistics.