Privacy

Last updated 3 November 2026

This page covers the Brennan Controller browser extension and realizerlabs.com, both run by Realizer Labs LLC. The other Realizer Labs products have their own pages and are not covered here. Questions, or a request to see or remove what we hold: brennan@realizerlabs.com.

Your music stays with you

The Brennan Controller talks to your Brennan B2 or B3 over your own network. Your library, the names in it and what you play are read from the Brennan into your browser and are not sent to us. The Brennan itself only speaks plain http, so that traffic is not encrypted; it stays on your own network.

What the extension sends, and when

• Registration, only if you buy or activate a licence. Your email address, the licence code, and a random install number the extension makes for itself. We use them to issue and check your licence, limit it to three computers, email you your code, and answer support requests. We also record what happened (for example activated, renewed, deactivated) with the date, a one-way hash of your network address and your browser's name and version, to stop abuse and to investigate problems. Payment is taken on the payment processor's own page; we never see your card details.
• Daily check-in. Once a day the extension sends its version, the random install number and whether the install is registered. It contains no email address, nothing about your music and nothing about your computer. We use it to count installs and the versions in use. The current version has no setting to switch it off.
• Playlist sync, off unless you turn it on, registered users only. The playlist names and the artist, album and track names in them (no music files, no listening history) are sent to us and stored compressed under your licence email, so your other registered computers can fetch them. Turning Sync off, or pressing Remove, deletes the stored copy. When a licence ends, its stored playlists are deleted 30 days later.
• Album art lookups, only when you run the Album art tool. The artist and album name go straight from your browser to Apple Music (itunes.apple.com) and MusicBrainz (musicbrainz.org), and covers are fetched from Apple, the Cover Art Archive or the Internet Archive. Those services see your network address and the search, under their own privacy policies. We do not see these requests.

What the extension keeps on your computer

Your settings, your Controller playlists, the Brennan's address, the random install number and your signed licence token are kept in the browser's own storage for the extension. Songs you play through your computer are kept in a cache whose size you choose in Settings and can clear. Uninstalling the extension removes all of it. Reinstalling counts as a new computer on your licence, so deactivate a computer in Settings first, or ask us to free its place.

Finding your Brennan

To find the unit the extension may try addresses on your own network, nothing outside it. You can switch the automatic search off in Settings and type the address instead. The extension does not read the pages you visit, your tabs or your browsing history.

This website

• Downloads. When you ask for a download we keep your email address and a record that you accepted the terms. If you tick the box we email you when a new version comes out; you can stop those at any time. We do not add you to any other list, and we do not sell or share your address.
• Support. What you write and any screenshots or videos you attach are stored with your support request and emailed to us, and kept for as long as is needed to help you and to keep a record of the problem. Mail you send to a Realizer Labs address may be read by our support system so that it can be filed with your request.
• Analytics. The site uses Google Analytics to count visits and see which pages are used. It sets cookies in your browser and sends Google your network address and page visits. You can block it in your browser or with a tracking blocker.

Where it is kept, and who else sees it

Our records are held with Google Cloud (Firebase) in the United States. Our hosting and email providers handle the data only to run the service for us. Apple, MusicBrainz and the Internet Archive receive the album art searches described above, and the payment processor receives what you enter at its checkout. We do not sell your information, use it for advertising, or share it for anyone else's marketing. Server logs kept by our hosting provider are held for a limited time (typically 30 days) and are used to keep the service running and to deal with abuse.

Your choices

You can turn playlist sync off, deactivate a computer from Settings to free its place, and uninstall the extension at any time. To have your licence record, synced playlists, download record and support messages deleted, write to brennan@realizerlabs.com from the email address concerned. We keep what the law requires us to (for example, payment records).

Changes

If this page changes, the date at the top changes with it.