Facebook's Fascination with My Robots.txt

For the past 4 days — and probably more since I don't have logs beyond that — Facebook has been hitting the /robots.txt of my self-hosted Forgejo instance several times per second. The user-agent is facebookexternalhit/1.1 (+http://www.facebook.com/externalhit_uatext.php) . I expected the UA header to be nontrustworthy, but all the requests are also coming from Meta's IP address ranges. The…