The goal of this prank is to scare someone, not to damage their device. Here is the safest and most effective way to do it:
A normal webpage with a URL bar at the top spoils the illusion instantly. You must hide the browser interface to make it look like a system-wide lock. Press F11 . On Mac: Press Control + Command + F .
However, the victory was short-lived.
: The browser or entire computer is often locked using an iframe loop or a system-level overlay that prevents the user from exiting or accessing the desktop. User Data Display
Press Ctrl + Shift + Esc to open the Task Manager . Locate your browser (Chrome, Edge, Firefox), right-click it, and select End Task . Fake FBI Lock Warining Screen Prank
When encountered randomly online, it is rarely a harmless joke. It is usually a (browser locker) or actual ransomware . Malicious variants are hosted on compromised websites, malicious ad networks (malvertising), or bundled with pirated software downloads. True ransomware will encrypt your actual files, whereas a browlock simply hijacking your browser application. How to Escape a Locked Screen
Most of these sites have a button to enter fullscreen mode (or you can hit The goal of this prank is to scare
: Simple websites use full-screen JavaScript to mimic the lock. These don't actually infect your PC and can usually be closed by hitting Alt + F4 or using the Task Manager.
: Features realistic Department of Justice (DOJ), FBI, or Homeland Security seals. Press F11