Excerpt from this article:
If you’ve never heard of the term before, “digital blackface” is used to describe various types of minstrel performance that become available in cyberspace. Blackface minstrelsy is a theatrical tradition dating back to the early 19th century, in which performers “blacken” themselves up with costume and behaviors to act as black caricatures. The performances put society’s most racist sensibilities on display and in turn fed them back to audiences to intensify these feelings and disperse them across culture.
… For while reaction GIFs can and do every feeling under the sun, white and nonblack users seem to especially prefer GIFs with black people when it comes to emitting their most exaggerated emotions. Extreme joy, annoyance, anger and occasions for drama and gossip are a magnet for images of black people, especially black femmes.
Now, I’m not suggesting that white and nonblack people refrain from ever circulating a black person’s image for amusement or otherwise (except maybe lynching photos, Emmett Till’s casket, and videos of cops killing us, y’all can stop cycling those, thanks). There’s no prescriptive or proscriptive step-by-step rulebook to follow, nobody’s coming to take GIFs away. But no digital behavior exists in a deracialized vacuum. We all need to be cognizant of what we share, how we share, and to what extent that sharing dramatizes preexisting racial formulas inherited from “real life.” The Internet isn’t a fantasy — it’s real life.