The unusual event was followed by an official Twitter account posting only a goat emoji in reply to the event.
Events began when Mr Dorsey followed a special account, known as Big Tech Alert, which tracks the activities of major tech bosses on Twitter. That decision appeared to be a specific attempt to draw attention to the account, and to make clear that the Twitter boss knew about it.
Moments later, the Mr Dorsey used his own platform to unfollow Mark Zuckerberg. He did not explain the decision, and there was no public interaction between the two.
As expected, that triggered an alert from the tracking page that announced that the Twitter boss was no longer following the Facebook founder.
An official Twitter account then replied to that alert with just a goat emoji.
There was no public interaction between any of the accounts before the unfollowing. It is still not clear whether it was the result of a genuine fallout or a more friendly jibe.
Mr Zuckerberg's Twitter account is hardly used at all, despite having more than 400,000 followers. While he used it throughout 2009 to write about new features, the only post since was a 2012 message that linked out to a post on his official Facebook page.
Mr Zuckerberg followed only one user of the site through the whole year – in another unexplained, unusual interaction. But that happened at the beginning of the year and is not thought to be related to any of the new events.
Some have speculated that the goat – and perhaps all of the events – are in reference to a strange exchange between the two billionaires at the beginning of the year.
In January, Mr Dorsey claimed that Mr Zuckerberg had served one of the animals as part of a meal, during a year when he was only eating food he had killed.
Mr Dorsey said that Zuckerberg is a “very, very smart businessman,” and then he went on to say: “He made goat for me for dinner. He killed the goat.”
The Twitter boss then clarified that Mr Zuckerberg did not kill the goat in front of him but “killed it before” their meal.
“I guess he kills it,” he said. “He kills it with a laser gun and then the knife. Then they send it to the butcher.”
Mr Dorsey then corrected himself to make clear it was probably a stun gun, and went on to suggest that he did not eat the goat because it was cold.
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