@JeffSchaller The problem appears to be that the t.ly either started using CloudFlare, or changed their configuration, such that the response we get back when we give them the honest User Agent of "SmokeDetector/git (+
github.com/Charcoal-SE/SmokeDetector)" doesn't indicate that the URL is forwarded, so trying to get the destination address just results in seeing the source address as the end destination. The response when a User Agent indicating that the requestor is Firefox
does indicate that the URL is a forward, and everything works. I've updated SmokeDetector such that we now lie and claim to be Firefox.