Shafiqah Hudson was looking for a job in early June of 2014, toggling between Twitter and email, when she noticed an odd hashtag that was surging on the social media platform: #EndFathersDay.

The posters claimed to be Black feminists, but they had laughable handles like @NayNayCan’tStop and @CisHate and @LatrineWatts; they declared they wanted to abolish Father’s Day because it was a symbol of patriarchy and oppression, among other inanities.

They didn’t seem like real people, Ms. Hudson thought, but parodies of Black women, spouting ridiculous propositions. As Ms. Hudson told Forbes magazine in 2018, “Anybody with half the sense God gave a cold bowl of oatmeal could see that these weren’t feminist sentiments.”

But the hashtag kept trending, roiling the Twitter community, and the conservative news media picked it up, citing it as an example of feminism gone seriously off the rails, and “a neat illustration of the cultural trajectory of progressivism,” as Dan McLaughlin, a senior writer at National Review, tweeted at the time. Tucker Carlson devoted an entire segment of his show to lampooning it.

So Ms. Hudson set out to combat what she quickly realized was a coordinated action by trolls. She created a hashtag of her own, #YourSlipIsShowing, a Southernism that seemed particularly useful, about calling out someone who thinks they are presenting themselves flawlessly.

She began to aggregate the trollers’ posts under it, and encouraged others to do so and to block the fake accounts. Her Twitter community took up the mission, including Black feminists and scholars like I’Nasah Crockett, who did some digging of her own and discovered that #EndFathersDay was a hoax, as she told Slate in 2019, organized on 4chan, the dark community of web forums peopled by right-wing hate groups.