Ephedrin

I can‘t see where Flightaware would take its information from except from the ADS-B exchange. Flightradar is a bit more detailed, you can see it quite well there: At some airports you can follow aircraft almost to the gates, at some they disappear right after leaving the runway. And sometimes they copilot simply forgets to turn off the transponder and they remain visible for minutes after reaching the gate. I can only assume but this sounds a lot like what the traffic does in MSFS.

ADS-B. Transponder off, signal off.