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.

Twitter, Ms. Hudson and others said, was largely unresponsive. Nonetheless, their actions were effective. #EndFathersDay was pretty much silenced within a few weeks, though fake accounts continued to pop over the years, and Ms. Hudson kept calling them out, like an endless game of Whac-a-Mole.

Yet #EndFathersDay, it turned out, was more than an absurd joke. It was a well-structured disinformation action, a kind of test balloon, as Bridget Todd, a digital activist who interviewed Ms. Hudson in 2020 for her podcast, “There Are No Girls on the Internet,” put it, for later actions, particularly the election disruption campaigns that began in 2016 with tactics replicated, as Senate hearings showed, by Russian agents. In hindsight, Ms. Hudson’s efforts added up to an early and effective bulwark against what continue to be threats against democracy.

“It should be validating,” Ms. Hudson told Slate. “But instead it’s been upsetting and alarming. Nobody wants to be right about how much real peril we’re all in, even if you saw it coming.”

Ms. Hudson, a freelance writer who had worked in nonprofits but from 2014 on dedicated herself to Twitter activism, died on Feb. 15 at an extended-stay hotel in Portland, Oregon. She was 46.

Her brother, Salih Hudson, confirmed her death but did not know the cause. She suffered from Crohn’s disease, he said, and respiratory ailments. Her followers, however, knew from her posts that she had long COVID and had recently been diagnosed with cancer. And that she had no money to pay for her care. Many pitched in to help.

At her death, her community mourned their loss, and expressed frustration and anger that Ms. Hudson had never been paid by the tech companies whose platforms she policed or properly attributed by scholars and news organizations that cited #YourSlipIsShowing, and that she had not received the health care she so desperately needed.

“The world owed Fiqah more than it gave her,” Mikki Kendall, a cultural critic and author of “Hood Feminism: Notes from the Women That a Movement Forgot” (2020), said by phone. Kendall is one of many Black feminists who took up Ms. Hudson’s mission and befriended her on Twitter, which is now called X. “The world owes Fiqah to never let this happen to anyone else again. Unfortunately, she exists in a long tradition of Black activist women who die impoverished. Who die sick and alone and scared. Because we love an activist until they need something.”

Shafiqah Amatullah Hudson was born on Jan. 10, 1978, in Columbia, South Carolina. Her father, Caldwell Hudson, was a martial arts instructor and author. Her mother, Geraldine (Thompson) Hudson, was a computer engineer. The couple divorced in 1986, and Shafiqah grew up with her mother and brother, mostly in Florida, where she attended the Palm Beach County School of the Arts, a magnet school.

Shafiqah earned a bachelor’s degree at Hobart and William Smith Colleges in Geneva, New York, in 2000, majoring in Africana studies with a minor in political science. After graduating, she moved to New York City, and worked at various nonprofits.

She was new to the city, and lonely. She found community on blogs and social media sites, including Twitter, which she joined in 2009. (She chose as her avatar an image of Edna Mode, the imperious fashion maven from “The Incredibles.”) And like many Black women on that platform, she was mocked and harassed. She received rape and death threats, she told Todd.

In addition to her brother, Ms. Hudson is survived by her father and her sisters, Kali Newnan, Charity Jones and Mosinah Hudson. Geraldine Hudson died in 2019.

In the last months of her life, Ms. Hudson posted about her deteriorating health and her fears about not being able to pay for her care or her housing. She was unable to work because of her disabilities.

She had moved to Portland, her brother said, because the climate was better for her respiratory ailments. But she was not able to secure health insurance. Doctors had discovered the painful fibroids from which she suffered were cancerous. She needed money for more biopsies, and for transportation to the hospital. Her Twitter community chipped in, as always. She did not ask her family for help.

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“She was very private and very proud,” Margaret Haynes, a cousin, said by phone, adding that she had spoken to Ms. Hudson a few weeks before her death. “She told me, ‘I’m good. If I need something, you’ll be the first to know.’”

Yet on Feb. 9, she told her followers: “I feel like I’m meowing into the void. And it’s raining. And I’m just trying not to drown.”

Feb. 7 had been a tough day. Ms. Hudson was dizzy, and in pain, she wrote. She was feeling her mortality, and posted about her decision to be single and not have children — “to be an Aunt(ie) and not a mom,” as she put it, recalling a conversation she’d had with a young family member, and rendering it with characteristic wit.

“Say Life on a particular plane of existence is dinner in a restaurant,” she explained, continuing, “Let’s say the life Auntie (me) has chosen is the Salad option. A life without partner(s) or Littles of my own. Let’s say the Soup option comes with Littles, and maybe a partner. But you can only choose one. Like. If you pick the Family Soup, you can’t have the Singlehood Autonomy Salad. ”

She riffed a bit in this vein, and then concluded, “Auntie Fiqah chose the Salad. Cuz she only kinda likes Soup. And no one can ever convince her that she REALLY likes Soup. Or will come to. Or that she should. Soup should be savored lovingly and enthusiastically. If it can’t be? Have the Salad.”

Ms. Hudson died eight days later.

This article originally appeared in The New York Times.