It's no secret that Donald Trump dislikes a lot of things. He makes it known on Twitter.

Last year, The New York Times compiled "the 319 people, places, and things Trump has insulted on Twitter" (though that number has grown since then). Among them were the paper of record itself, Hillary Clinton, the Tony-winning musical "Hamilton," 20-time Oscar-nominated actress Meryl Streep, and retail giants like Macy's and Amazon.

A group of anonymous activists have decided this makes him a bully. On March 16, they launched the " target="_blank"Block the Bully" campaign, and an application that automatically un-follows and blocks Trump on Twitter. Users can then choose to share the campaign with their Twitter followers, and explain why they did it.

Anyone can un-follow Trump at any time without an app. But "Block the Bully's" creators hope the effort will turn into a widespread movement.

"Of Trump’s 26 million Twitter followers, fewer than half actually voted for him. The majority are people like us — citizens who want to see what our president is up to and, candidly, can’t look away from what we perceive as the train wreck that his is presidency so far," they said in a press release. "But what if we did look away? What if tomorrow Donald Trump woke up and saw his following cut in half?"

Here's how "Block the Bully" works.

A group of anonymous activists (who say they work in tech and entertainment) launched the Block the Bully campaign on March 16. The team calls itself "the Resistance."

To get started, participants need to make sure they're signed into Twitter. Then they go to the Block the Bully site, and click the "connect" button.

Source: Block the Bully

Once they authorize the app, it automatically un-follows Trump, and blocks him (meaning they won't see any of his tweets on their feeds, and he can't reply or DM them).

Even if participants are not following @RealDonaldTrump, clicking "connect" on Block the Bully will automatically do it for about one second, before immediately unfollowing him.

They'll then have the option to share that they've blocked Trump.

A few hours after the launch, users started tweeting that they joined the campaign.

"Since taking office, the president has continued to use his Twitter account to bully opponents, spread misinformation, and undermine faith in American institutions," the campaign creators said. "We let him get away with it by following him, retweeting him, replying to him, even when we do so in disbelief and disgust. He feeds off the attention. We need to change our own habits in order to defang him."