A boardview (component placement) file (board DA0R05MB8D0). Shared as “AFS da0r05mb8d0-d-muse.brd.rar” — a .rar file, 6.91 MB.
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 @afsbiosfree. Enginerys does not host this file.
How to open a .rar file
Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.
7-ZipWinRARThe Unarchiver (macOS)