https://arstechnica.com/gadgets/2019/01/youtube-updates-policies-to-explicitly-ban-dangerous-pranks-challenges/

Pranks and challenges have always been popular on YouTube, but now the Google-owned company has set stricter guidelines for such content. A new YouTube support page details that the company updated its policy surrounding "harmful and dangerous" content to explicitly ban pranks and challenges that cause immediate or lasting physical or emotional harm.

"YouTube is home to many beloved viral challenges and pranks, like Jimmy Kimmel’s Terrible Christmas Presents prank or the water bottle flip challenge," the FAQ post says. "That said, we’ve always had policies to make sure what’s funny doesn’t cross the line into also being harmful or dangerous."