More like a fourth J-20 was in that parking space?
Yes our old SR-71 used to "weep" JP fuel around where it sat as the tanks wouldn't seal completely until it was hot and fast, and it was said that you could see the outline of it on the ramp after it would pull away. In fact anecdotally the SR had to slow down to re-fuel from the KC-135s, as it slowed below super-sonic the aircraft cooled and the tanks would unseal and start to weep fuel even as it was being refueled, JP-7 is very kool fuel, and had a very low volatility number so no one worried about it "flashing off".
a cloaked Klingon Bird of Prey
Indeed!, I would concur! very little doubt about that??? and where else would you catch such a bit of news as on the Sino Defense Forum??