The term became popular among "grey hat" marketers looking to spy on competitors. Because Bitly links are often used to track clicks (conversions), aggressive marketers want to know exactly where their competitors are getting their traffic. "mfixer1" is often associated with scripts or techniques that allow users to uncover the destination of obscured links or analyze the traffic data of public links.
: Most users encounter this link when looking for "fixer" tools—scripts or software designed to patch specific bugs in operating systems or games. bitly mfixer1
Probably safe, but verify the GitHub repo’s reputation. The term became popular among "grey hat" marketers