A boardview (component placement) file (board LA-J621P). Shared as “LA-J621P r1.0.bdv” — a .bdv file, 981 KB.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @ShareMan_Electronic_Files. Enginerys does not host this file.
How to open a .bdv file
Text-based boardview produced by Honhan / Hon Hai test tooling, with lightly obfuscated content.
OpenBoardViewFlexBVBoardViewer