Bookmark Manager Zero gives your Firefox bookmarks the upgrade they needed — without changing how you already use Firefox.

Bookmarks Identify as live, broken/unreachable, or parked sites.
Stay safe with multiple layers of security checks indicating whether your bookmarks are safe, suspicious, or malicious (with tool-tips explaining why!).
Add, edit, or move a bookmark in Firefox or Bookmark Manager Zero. Changes made in one will reflect in the other instantly.
No importing, exporting, accounts, or extra steps.
Everything stays perfectly in sync with your native browser bookmarks.

What it does: Scans bookmarks in your expanded folders every 7 days and re-scans whenever folders are expanded. You can re-scan anytime if desired. If a previously safe bookmark now flags as suspicious or malicious, the add-on will alert you. Checks if your bookmark links are reachable Indicating if the links are live, broken/unreachable, or parked domains (parked typically means they are for sale or currently ad farms) Optional Integrated Support for VirusTotal, Yandex, and Google Safe Browsing scanning with your own API key. (keys stored locally with AES-256-GCM encryption. Duplicate Bookmark Detection This function scans your bookmarks for duplicates and helps you tidy them up: individually or in bulk!. Preview Images Hover the mouse over your chosen bookmark to generate a small image of the web page Undo Your Mistakes! — Deleted something by accident? No need to panic! — you have a 5-second undo window before the change reaches Firefox Customizable Interface Multiple Themes, Text and Accent Colors, Layouts, Scaling Options, and freedom to use your own background image if you so desire. Fast search, advanced filtering, and drag-and-drop organization Privacy first: This extension never collects, stores, sends, or tracks anything. No analytics. No external servers. No data sharing. Everything stays on your device. 100% free. 100% local. 100% yours. A safer, cleaner, smarter way to manage Firefox bookmarks — built to respect your online safety and privacy. Developer Note: There are no perfect add-ons (other than perhaps UBlock Origin). Your mileage with this one may vary but i've done my absolute best to make this add-on as robust, functional, and user friendly as possible. Link checking and security scanning rules work as i've written them but the internet is a complex ever-changing beast and as such it's not unlikely that you will experience false positives as well as false negatives. Bookmark Manager Zero is meant to be a tool to help keep you safe online. The rules used for scanning (as well as the entire source code) are entirely available on the github for anyone interested: https://git.absolutezero.fyi/AbsoluteXYZero/BMZ-Firefox/