Context:

Pekora was doing the exploding-a-watermelon-with-rubberbands thing, and the moment it exploded it knocked her stream offline, presumably because something hit her pc.
The livestream kept looping the explosion continuously while she was working on getting the stream back online.

The archived stream has a big jumpcut, but thankfully the footage survived.
YouTube:【輪ゴムでスイカ割り】何本で割れるか検証する！！！！！！！！！！！！ぺこ！【ホロライブ/兎田ぺこら】 @ 1:30:50