Marketplace Listing AssistantPrivacy
Marketplace Listing Assistant · last updated 17 October 2026
In short: everything the extension saves stays in your browser. It has no servers, no accounts, no analytics and no tracking, and it never sends your listings or photos to the developer or to anyone else. The only thing sent outside Facebook is what's needed to unlock the paid version, if you buy it: your license key (to Polar) or your purchase email (to our unlock service, which emails you a sign-in code).
What it stores, and where
In your browser's local extension storage, on your computer only:
- Listings you choose to save: the details from each listing's Facebook Edit page (title, price, category, description and other fields) and copies of its photos.
- What it reads from your own Selling page, Insights and Seller dashboard when you open them: each listing's status, price, listing date and click count, and your account totals (clicks, saves, shares, followers, rating).
- Your settings, queue, snippets, saved views, notes, and the history and earlier versions of each listing.
What it sends
Apart from the optional license check below, nothing leaves your browser except what Facebook needs to show you its own pages. The extension works inside facebook.com pages you open, and downloads your listings' photos from Facebook's image servers (fbcdn.net) to save copies.
Payments (optional). The lifetime unlock is sold through Polar, the merchant of record, which handles checkout, payment details, tax and receipts under its own privacy policy. The extension never sees your payment details. When you enter a license key, the extension sends the key and a device label (e.g. "Chrome · 2026-10-17") to Polar's license API to activate it, and re-checks it about once a week. It keeps the key, Polar's activation ID and the purchase email Polar returns in your browser.
Sign in with your purchase email (optional). Instead of a key, you can enter the email you paid with. It's sent to the unlock service (a small server run by the developer on Cloudflare), which asks Polar whether that email bought the unlock and, if so, emails you a 6-digit code through Resend. The service keeps the code (hashed) for 10 minutes and short-lived request counters to prevent abuse; it doesn't keep your email address. The extension stores a signed sign-in token and your email, and re-checks the token about once a week. No other website is contacted. Backup and spreadsheet files are only created when you click Download, and go where you save them.
Permissions
- facebook.com: to read and fill the Marketplace pages you're on (your Selling page, Edit and Create pages).
- fbcdn.net: to save copies of your listings' photos.
- Storage (and unlimited storage, for photos): to keep your saved listings in your browser.
- Alarms and notifications: for the optional daily reminder when listings are due, and the weekly license re-check. Reminders never post anything.
- api.polar.sh: to activate and re-check a lifetime license key, only if you enter one.
Deleting your data
Remove a listing in the dashboard to delete it and its photos. Removing the extension from Chrome deletes everything it stored. Files you downloaded (backups, spreadsheets) stay on your computer until you delete them.
Children
The extension is meant for Facebook Marketplace sellers and isn't directed at children.
Contact
Made by Nikita Kostin. Questions: nikitakostin.com. See also the terms.
Marketplace Listing Assistant is an independent tool. It is not affiliated with, endorsed or sponsored by Meta Platforms, Inc. Facebook and Marketplace are trademarks of Meta Platforms, Inc.