Browser extensions (Safari & Chrome)

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 during an AI Focus block they keep track of your open tabs so FocusDragon can close a distracting one and offer the rest back later.

URL-level blocking inside Safari, Chrome/Chromium and Firefox
Faster, more precise tab blocking than DNS alone
A handshake with the Mac app so FocusDragon can tell the extension is actually on

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.

If "All Websites" is not set to "Allow", the Safari extension can't block anything. This is the single most common Safari setup miss.

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, Opera, Vivaldi and Chrome for Testing; install it from the Chrome Web Store from inside those browsers. Arc and a few other browsers cannot be enforced reliably and may be closed during a website block — see Browser Setup.

Firefox

Install the FocusDragon extension from Firefox Add-ons (addons.mozilla.org/addon/focusdragon). Once installed, Firefox gets the same URL-level blocking as Safari and Chrome, and works with AI Focus.

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 on your Mac. You don't have to configure any of this; it's automatic. AI Focus uses it to keep track of your open tabs. Every AI Focus check is judged from a screenshot either way, so the bridge never changes what the dragon decides.