Hmm, the user is possibly trying to enable see-through effects on macOS Sierra using the Seethrough MP4 version. But wait, Seethrough is a patch or feature, not an MP4 file. Maybe the user confused an MP4 file with a kext installer. MP4s are videos, so maybe they're looking for an installation guide in video format. Alternatively, they might have found a video tutorial and need help understanding it.