In short, you are likely looking at a "footprint" left by an automated redirecting through a service to ensure the content is served over a secure connection.
: Often serves as a status code, a timestamp fragment, or an internal routing identifier within these types of automated logs. In short, you are likely looking at a
: This is a standard HTTP request header that tells a server the browser prefers an encrypted (HTTPS) connection and can automatically "upgrade" insecure links to secure ones. a timestamp fragment
: This is a known domain often used for ad tracking or analytics redirect services. In short, you are likely looking at a