TugStopper by Little Dunk Studio

TugStopper is a content blocker designed to help people in recovery from pornography addiction.

What it does:

Blocks 75,000+ adult and explicit websites automatically
Enforces safe search on Google, Bing, DuckDuckGo and YouTube
Shows a motivational blocked page with your domain name when a site is intercepted
Syncs your blocklist and custom rules from the TugStopper desktop app (Windows) in real time
How it works:
The extension checks every URL you visit against a built-in blocklist. If a match is found, you are redirected to a blocked page instead. No browsing data is ever sent to our servers, all filtering happens locally on your device.

Note: Active blocking requires the free TugStopper desktop app to be installed and running. The extension popup will show "App offline" if the desktop app is not detected.