It has been a while since we saw some pony sneak into the world of other cartoons, but there are apparently still a few fans out there hiding their favorite characters in the backgrounds of things! Netflix's conspiracy filled "Inside Job" dropped a Rarity off, with a more G1 style, along with possibly a Pinkie Pie as well, though the mane doesn't match as closely. This happens on the 5th episode of the series.
Thannks to PL for the screencap!