Debates over privacy have plagued Facebook for years.

But the news that Cambridge Analytica, a political data firm that worked on President Donald Trump’s 2016 campaign, was able to gain access to private data through the social network has sparked an unusually strong reaction among its users.

The hashtag #DeleteFacebook appeared more than 10,000 times on Twitter within a two-hour period Wednesday, according to the analytics service ExportTweet. On Tuesday, it was mentioned 13,466 times, according to the analytics service Digimind.

Cher was one such deserter, writing on Twitter that the decision to quit Facebook, although “very hard,” was necessary because she loves the United States. Brian Acton, a co-founder of the WhatsApp messaging service, told his tens of thousands of followers to delete Facebook — the very social network that acquired it in a $19 billion deal in 2014.

For people who aren’t celebrities or billionaires, the decision to abandon Facebook came reluctantly, because the platform often served as their sole connection to certain relatives, friends and professional opportunities.

For people like Richard Perry, a filmmaker in Los Angeles, Facebook is a business partner of sorts. For a long time, Perry had wanted to leave Facebook. He never felt comfortable knowing the company had access to much of his personal information. In the months before the 2016 election, he watched the social network become what he called “a garbage platform of ads and weird reposted articles and people that you care about exposing themselves as racists.”

But it was also where Perry promoted his films, where he posted ads seeking help on the set and where he communicated with colleagues and a “massive number” of friends and relatives.

Until he heard about Cambridge Analytica. “I suspected this stuff was going on, but this is the first time it’s been plainly exposed,” he said. “It seems so malicious, and Facebook seems so complicit all the way up and down, like it doesn’t care about its users.”

Perry, 39, has since deleted his profile and plans to switch to Twitter and Instagram for his social media needs. “It was an easy decision,” he said. “It’s not going to be the end of the world.”

Another user, Dan Clark, a retired Navy veteran in Maine, kept one Facebook account to chat with friends from all over the world and a separate account to keep tabs on members of his family nationwide. But this week, he deleted both accounts.

“Facebook was the main platform I used to keep in touch with all of them, and it was a difficult decision to give it up,” said Clark, 57. “But you have to stand for something, so I just put my foot down and said enough is enough.”

Before cutting the cord, Clark posted on Facebook inviting his contacts to ask him for his personal phone number. More than 100 people reached out within three days.

“There are just so many ways nowadays to stay in contact: phones, email, instant message, Gab, which is a social network that doesn’t censor anything,” he said. “Facebook is more obsolete than people would think.”

A sell-off in Facebook shares has amounted to almost $50 billion in market capitalization evaporating since the start of the week. The stock fell 1.5 percent before the opening bell Wednesday and, after falling 9 percent, it’s one of the worst weeks in company history.