White House rivals Hillary Clinton and Donald Trump have poked fun at each other at a charity dinner, a day after their bitter duel on the debate stage.

She laughed as Mr Trump joked about her well-paid speeches and the FBI investigation into her private email.

But the Republican was booed when he joked that his Democratic opponent hated Roman Catholics.

Yet Donald Trump has a very real Utah problem. And it's largely because of one relatively unknown candidate: independent Evan McMullin.

McMullin, according to a raft of recent polling in the Utah, is surging in the state.

For their part, Trump's advisers don't appear publicly concerned about the state.

Affected sites included Twitter (TWTR, Tech30), Etsy (ETSY), Github, Vox, Spotify, Airbnb, Netflix (NFLX, Tech30) and Reddit.

"If you take out one of these DNS service providers, you can disrupt a large number of popular online services, which is exactly what we're seeing today," said Jeremiah Grossman, chief of security strategy at cybersecurity startup SentinelOne.

The massive outage drew the attention of the FBI which said Friday that it was "investigating all potential causes" of the attack.

When he takes the debate stage, he does not smile.

The closest thing to it is a sore-loser sneer for failing to get an Emmy out of a reality television show that allowed him to belittle women. He tries to act normal — to hold back the hatred inside him. But this dangerous man is incapable of bottling up his dark self for a full 90 minutes.

The best presidents are aspirational, urging us to climb every mountain and ford every stream. Trump has never been able to make it out of the gutter.