It checks for:

dead/parked links

suspicious redirects

changes in domain behavior

duplicates

optional integration for user-supplied API keys for VirusTotal / Google Safe Browsing / Yandex

It also keeps 7-day cached results and alerts you if a previously safe bookmark becomes suspicious. All analysis runs on-device and the code is fully open source.

Firefox: https://github.com/AbsoluteXYZero/Bookmark-Manager-Zero-Fire...

https://addons.mozilla.org/en-US/firefox/addon/bookmark-mana...

Chrome: https://github.com/AbsoluteXYZero/Bookmark-Manager-Zero-Chro...

https://chromewebstore.google.com/detail/bookmark-manager-ze...

Chrome Web Store reviews lag behind, so the Chrome version is currently one release behind Firefox.

Known limitations: relies partially on external plaintext blocklists → possible false positives/negatives. Preview images are fetched via the public mShots screenshot service (nothing else leaves the browser).

Feedback appreciated.