French President François Hollande attends a meeting with leaders of international start-up companies based in Paris during the French Tech Ticket conference Wednesday. (Philippe Wojazer/AFP/Getty Images)

Beware the Internet. Or at least know how to disable an app function. French President François Hollande just learned that the hard way.

Hollande’s recent visit to an Internet company, which his advisers thought would be cool to live-stream on Periscope, a popular video app, turned into a public relations disaster after viewers were allowed to post comments on-screen in real time.

Hundreds of viewers went after the president’s expanding waistline, his sex life, his fashion sense and his actions on French unemployment.

One poster said Hollande’s increasing girth suggested that a disproportionately large amount of France’s tax revenue was being diverted to his food bill.

Another commenter said Hollande’s salary — 178,920 euros a year (about $196,000) — was clearly not enough, because he did not seem able to afford full-length suit pants. The poster called for the creation of a special French fund to buy four inches of cloth to extend the pants to cover the president’s ankles.

“Laugh until you die,” one posted, according to a Thursday report from the London Times newspaper. “He doesn’t know what he’s talking about. He’s completely lost.”

“Did he come on a scooter?” another viewer wrote, a reference to photographs of Hollande arriving on a scooter to visit his onetime alleged mistress, French actress Julie Gayet, in 2014. The paparazzi photos of Hollande arriving on the scooter tarnished the president’s reputation and precipitated his split from his then-partner, Valérie Trierweiler, who later wrote a tell-all book about the French leader.

The French newsmagazine Le Nouvel Observateur, called the 24 minutes that the unrelenting insults could be viewed on Periscope, which is owned by Twitter, an online catastrophe for the 61-year-old president.

And it seems it all could have been avoided by enabling a function that allows users to block unwanted comments, news reports said.

At first, the president’s aides, who apparently thought it would be hip to showcase Hollande’s visit to the headquarters of an online fashion store, ShowroomPrive.com, tried to erase the most offensive comments. But they were quickly overwhelmed by the sheer volume of insults hurled at the French leader.

After almost half an hour, his staff managed to switch the broadcast to the presidential Elysee website, where comments can be filtered.

But the damage was done. Several thousand people commented, hundreds of them obscuring their identities with pseudonyms.

The barrage of criticism reflected Hollande’s abysmal approval rating, which has fallen to a record low of 17 percent, according to the Elabe polling institute. The Socialist leader, whose term expires next year, has taken a beating in the polls and in the French legislature over unemployment — now running at 10 percent — and his plans to overhaul labor laws, which currently stipulate a 35-hour workweek.

Public relations expert Philippe Moreau-Chevrolet was quoted as saying that the Periscope episode undermined the dignity of the French presidency — and, perhaps worse, highlighted the sheer amateurishness of Hollande’s staff. Far from showing the president as hip and modern, it instead demonstrated an ignorance of social media, the PR expert said, according to the Times.

It wasn’t the first time that Periscope got the better of a public figure — as French Internet users know well. A prominent French soccer player was broadcast insulting his manager and teammates on the live-streaming app last month.

William Branigin in Washington contributed to this report.

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