Cylance, Clam, Antiy-AVL, and Jiangmin (and also Norton at times) have done "False Positives" frequently over the years and is often the only one getting a hit when the others are undetected on virustotal or in the antivirus clients. It looks like it is having a issue with 7zS.sfx (look in details on page) which is the 7-ZIP self extractor used since early on and these mentioned antivirus get the occasional false positive hit on that. Firefox setups for Windows have been self-extracting 7z since Firefox 0.8 (Feb 2004)