While there isn't an official Apple document specifically titled "Long Paper" for Final Cut Pro 10.6.5, that version (released in October 2022) introduced several key stability and performance updates that are often discussed in technical guides and user documentation.
: Supports significantly faster exporting of H.264 and HEVC video formats on Mac computers equipped with Apple silicon (M1 and M2 series). Ambient Light Support final cut pro 10.6.5