Privacy Screen Overlay от magnets

Working somewhere people can see your screen? Privacy Screen Overlay drops a solid layer over the current tab so nobody around you can read it — perfect for opening WhatsApp Web, email, or chats on a laptop in the office.

Features:
• Solid overlay with adjustable opacity and any color you like (default black).
• Toggle privacy on the current tab from the toolbar button or a keyboard shortcut.
• Raise or lower the overlay opacity with keyboard shortcuts.
• "Reveal while hovering" mode: the overlay clears while you're actively looking at the page and re-covers the instant you look away or switch tabs.
• Sensitive sites list: add a domain (e.g. web.whatsapp.com) and it's covered automatically every time it loads.

Default shortcuts (all changeable at about:addons → Manage Extension Shortcuts):
• Toggle privacy — Ctrl+Shift+Y
• More opaque — Ctrl+Shift+.
• Less opaque — Ctrl+Shift+,

Your settings stay on your device. The extension collects nothing and sends no data anywhere.