Why you need them
DNS-level blocking via /etc/hosts is blunt — it blocks whole domains, which is fine for "no twitter.com" but doesn't cover "YouTube is allowed for tutorials but not for the homepage feed". The browser extensions add URL-level blocking, and they're also what reads a short DOM text excerpt from the active tab to ground the AI classifier when the screenshot is ambiguous.
- URL-level blocking inside Safari and Chrome
- DOM text excerpt fed to the AI classifier as a supplement to the screenshot
- Per-tab close behavior when the AI catches a drift (Hard / Nudge intervention)
Safari
The Safari extension ships inside the FocusDragon app — there's nothing extra to download. Enable it with:
- Open Safari.
- Safari menu → Settings → Extensions.
- Check the box next to FocusDragon.
- Click "Edit Websites" and set "All Websites" to "Allow".
- If you use Private Browsing, tick "Allow in Private Browsing" too.
Chrome (and other Chromium browsers)
Install the FocusDragon extension from the Chrome Web Store — the FocusDragon app's Extensions screen has a direct link, or search "FocusDragon" in the Web Store. The same extension works in Edge, Brave, Arc, and Opera; install it from the Chrome Web Store from inside those browsers.
Firefox
Install the FocusDragon extension from Firefox Add-ons (addons.mozilla.org/addon/focusdragon). Once installed, Firefox gets the same URL-level blocking and AI page-text coverage as Safari and Chrome.
Verifying it's working
Start a test block that lists a single site, hit Start, and visit that site in the browser. You should see the FocusDragon block page instead of the site. If the site loads normally, double-check the extension is enabled and (in Safari) that "All Websites" is set to Allow.
The native-host bridge
Under the hood, the Mac app and the browser extension talk through a small native-messaging bridge: the app exchanges page-content requests and responses with the extension's native host. You don't have to configure any of this — it's automatic — but if the extension can't reach the bridge, AI classification falls back to screenshot-only.