Chrome extension

The same guard, over every tab.

The extension runs the detector in the background and drops the blur on whichever tabs you have open. Email, banking, the wrong document in the wrong meeting. Nothing is uploaded; the face model ships inside the extension, and the only thing it ever sends anywhere is your license key, once a day, to confirm the subscription.

Download for Chrome (v1.2.0)Works in Chrome, Edge, Brave and other Chromium browsers. About 4 MB.

Free for 30 days, then $2.99 a month or $19 a year. Not on the Chrome Web Store yet, so it installs as an unpacked extension. Five steps, two minutes.

Install

  1. 1

    Download and unzip

    Grab the zip below and extract it somewhere it can stay, such as Documents. Chrome loads it from that folder.

  2. 2

    Open chrome://extensions

    Paste that into the address bar. Turn on Developer mode with the switch in the top right.

  3. 3

    Load unpacked

    Click Load unpacked and pick the folder you extracted. ShoulderSurf appears in the list; pin it from the puzzle-piece menu.

  4. 4

    Allow the camera

    The settings page opens on install. Click Allow camera and accept the prompt. Chrome only lets an extension ask from a visible page, so this happens once.

  5. 5

    Flip the switch

    Open the toolbar popup and turn protection on. Every tab is now covered. Use the popup to pause, or tweak reaction speed.

What it asks for, and why

Camera
To see whether a second face is looking at the screen. Frames are analysed in memory and discarded; there is no upload path in the code.
Read and change data on all websites
Chrome's wording for “can draw on any page”. The extension needs it to place the blur over whatever tab you are in. It reads nothing from the pages themselves.
Storage
Your settings, trial start date and license key, synced with your Chrome profile so they follow you between machines.
shouldersurf.ftmq.com
Once a day the extension sends your license key here to confirm the subscription is active. That is its only network request. If you are offline it keeps working for a week on the last answer.

Prefer not to install anything? The web guard protects its own page with no install, which is enough for notes and documents you open inside it.