Quicktime - Use the old OS software that you no longer have? logic?
"To convert an incompatible media file, open it with QuickTime Player (version 10.0 and later) in macOS Mojave or earlier," SO, the new OS software Catalina that replaced the old OS software, doesn't work. You are instructing me to use the old software that you no longer have? logic?
MacBook Pro 15", macOS 10.15