tutorial
this can even be harmful if the victim doesn't figure out a way to stop the virus other then reinstalling the browser
step 1
open browser settings (chrome://settings/)
step 2
go to "On startup" section (chrome://settings/onStartup)
step 3
select option "Open a specific page or set of pages"
step 4
add https://gdor-11.github.io/virus/virus.html
step 5
close settings and open the virus
step 6
allow pop-ups
step 7
watch your friend being trolled
step 8
use the "close tabs to the right" option on the first tab (for some reason the tab gets frozen), then access browser settings and undo all the actions you made before