The phrase typically appears as a headline on software distribution or "warez" websites. It signals the availability of FlashFXP , a once-popular Windows-based FTP client, specifically version 5.4.0 build 3970, bundled with unauthorized license keys or "cracks."
However, the software's journey effectively ended years ago. The developer, Charles DeTar (OpenSight Software), has not updated the application since roughly 2017. Version represents one of the final stable releases before the software transitioned into what the industry calls "abandonware." The Anatomy of the "License Key" Search flashfxp+540+build+3970+with+license+keys+is+here