Local first: your profiles stay on your computer

Mosaic has no cloud copy of your profiles. Every profile, cookie jar, proxy, saved login and two-factor secret is stored in one folder on your computer, and our account server never receives any of it. On a Mac that folder is ~/Library/Application Support/mosaic.

Why keep it local

An anti-detect browser holds the logged-in sessions for every account you run. In a cloud product, those sessions sit on the vendor's servers so they can sync between computers and teammates. That is a real feature, and it also means one company's database holds the keys to all of your accounts at once.

Mosaic takes the other side of that trade. There is no sync server, so your profiles and cookies are not on our servers to leak or lose. Our account server knows your email, your plan, your computers and when a profile opens, by a random id, and nothing that is inside a profile. Your accounts' cookies exist where the browser that uses them runs.

What is on disk, and how it is protected

The store and the cookie jars are encrypted on disk. Turn on app lock and nothing decrypts without your password, so a copied disk is ciphertext.

We would rather be exact about the case without app lock. The data key then sits in a file beside the data, readable only by your user account. That protects your profiles from other users on the same computer, and it stopped a measured attack that read cookies through a fake keychain. It does not protect against someone who copies your whole user folder. If that is your threat, turn app lock on.

Credentials, including the setup keys for two-factor codes, live in each profile's own vault. The companion inside each profile's browser shows the logins and codes for that profile and no other.

How it works: Local first

Downloads kept apart

Each profile's downloads go into its own folder, kept out of Spotlight and deleted with the profile. In an ordinary browser every file lands in one Downloads folder, where an invoice from one store sits beside a report from another, in the search index, for years after the account is gone. This is separation, not encryption: the browser writes the files itself, and we do not call them encrypted.

Backups and the trash

Mosaic takes a daily snapshot of the library and keeps seven days of them by default. A trashed profile stays recoverable for 30 days. Trashing a profile also closes its browser, so a profile you deleted is never still open on its proxy, writing cookies.

What does reach the internet

Being local does not mean offline, and the list is short enough to write out:

• your plan: a signed statement from our account server, refreshed periodically
• opening and creating profiles: each launch is authorised by our server with a short-lived ticket, and each new profile is counted, by a random id only. Pro keeps opening profiles for up to 24 hours without a connection; Free needs to be online
• the engine download, when you install or update Tesseract Chrome
• update checks for the app, which install only when you press the button
• your profiles' own browsing, which goes out through each profile's proxy, as it should

Proxy checks go through the proxies themselves. Profile names, fingerprints, cookies, logins and your proxy list are not sent to us.

What it costs you

A profile lives on the computer that made it. You cannot open it from a second computer, and there are no team seats or shared workspaces, because there is nowhere shared to put them. You can move profiles by exporting and importing Mosaic's own archive. If several people need to work the same accounts at once, a cloud product will fit better; Mosaic vs Multilogin sets out that trade against one of them.

Keeping everything local is also why Pro has no per-profile price: a profile runs on your hardware and costs us nothing to give you. Why Mosaic has no per-profile pricing explains the reasoning, and the pricing page has the plan.