Is Bookface Companion safe?

Medium risk

Bookface Companion sends Gmail thread participant email addresses to Bookface when Gmail conversations load.

When a Gmail conversation loads, Bookface Companion reads participant email addresses from the page and posts them to Bookface endpoints for investor and candidate context. When LinkedIn pages are viewed, it also sends the current LinkedIn profile URL to Bookface for related context.

Part of this rating comes from analysis signals we haven't published as detailed findings yet.

Y Combinatorv2.5.1Chrome Web Store
40Risk
Who publishes it

Y Combinator - no other listings under this identity

What this publisher told the store about itself, and the other listings that told it the same thing.

Publisher
Y Combinator
Declared legal entity
Y Combinator
Registered address
335 Pioneer Way, Mountain View, CA 94041-1505, US
Registered contact
Y Combinator Management, LLC

AI-generated. Findings may contain errors. Those marked Verified have been manually reviewed.

Publishers can request a review.

What it can do

Permissions this extension asks for, as declared in version 2.0.8. Asking for a permission is not a finding on its own - it is what the extension can do if it chooses to. The current listed version is 2.5.1, which we have not unpacked yet.

  • Read and change your data on bookface.ycombinator.com

    https://bookface.ycombinator.com/*

  • Read and change your data on bookface.code.yclocal.com

    http://bookface.code.yclocal.com/*

  • Store data in your browser

    storage

  • See the address and title of every tab you have open

    tabs

Where it sends data

Destinations our analysis observed Bookface Companion contacting. Sending data somewhere is not a finding on its own - an extension that syncs your settings has to talk to its own server - but it is where your data can go, and who else it goes to.

  • bookface.ycombinator.com

    Bookface Companion sends data to bookface.ycombinator.com. No other extension we have analysed sends data here.

Updated 30 September 2026bffjoheaobiobcocbgpehhegifipbbdp