You’re correct: UPX was initially implemented to reduce the size of executable files, which was a feature requested by some of our clients. However, as you’ve pointed out, the modern context of faster download speeds and increased storage capacity has made this less of a priority. In response to your question about antivirus programs, it’s true that UPX compression can sometimes trigger false positives. We’re aware of this rare issue and we’ve included an option to disable UPX compression in XL…