CopyRender captures the scene's render engine, its render settings (resolution, output path, file format, FFmpeg and stereo output), color management (view transform, display and sequencer colorspace) and the Cycles and Eevee engine settings. Only writable values are read. On paste, each value is matched back by name, so settings your Blender version doesn't recognize are skipped instead of throwing an error.

Copy and paste use Blender's own clipboard. On macOS, if Blender's clipboard doesn't carry the full payload, CopyRender falls back to the system pbcopy and pbpaste so nothing is truncated on the way through.