Umbra - A privacy screen that watches for your attention

Hey Product Hunt! 👋 I'm Sihab, and I built Umbra. The problem: I kept turning to talk to someone, or glancing at my phone, while messages, code or a bank tab sat wide open on my screen. Privacy filters and "lock your PC" habits don't help in those five-second moments. What Umbra does: it uses your webcam to notice when you stop looking at your screen, and covers it within about 0.7 s: a blur, your own image, a GIF/video or a solid colour. Look back and it's gone in about 0.15 s. The demo is a real recording of me doing exactly that. How it works: Google's MediaPipe face landmarker runs on your PC and measures head direction and eye gaze about 15 times a second. A one-minute calibration has you look at your screen edges and then away, so the limits fit you, your chair and wherever your camera sits. Privacy was the whole point: frames are processed in memory and thrown away. Nothing is recorded, saved or uploaded, and the whole thing is open source (GPL-3.0), so you don't have to take my word for it. It's free for Windows 10/11. Press F8 to toggle it, or pause it from the tray. I'd love to know: when would you want your screen hidden? And what should come next: a Mac version, auto-lock after longer absences, or per-app rules?