How sync works

Sval syncs without an account. It syncs through any folder you choose. That can be a cloud folder like iCloud Drive, Dropbox, or OneDrive, a network drive, or a USB drive. Sval doesn’t run a sync service.

The folder

Each of your devices writes its changes to the folder and reads the others’ changes from it. Whatever moves the folder between your devices moves your Workspaces too: your cloud service, your network, or you carrying the drive.

Sval keeps its files in a folder called “sval” inside the one you choose. Nothing else in your folder is touched.

Every device keeps a full copy of your Workspaces of its own. The folder is where the copies meet. So Sval works the same when the folder is out of reach, and catches up once it’s back. When you stop syncing on a device, the device keeps everything it has.

A cloud folder can take a few minutes to carry a change from one device to the other. Sval can only sync as fast as the folder does.

The encryption

Everything Sval writes to the folder is encrypted with your sync key. Your cloud provider, or anyone else who opens the folder, sees files it can’t read.

The first device you sync makes the key. Each device keeps the key, or what unlocks it, in the system’s own store for secrets: the Keychain on a Mac, Windows Credential Manager on Windows, and your keyring on Linux. A computer with no keyring keeps the key in your Sval profile.

Nobody can recover the key for you, Sval included. While one of your devices still syncs, that device holds the key and can give it to the others. A backup matters when every device is gone at once. You set up Sval on a new device, choose your sync folder, and paste the backup in place of a code. See Back up your sync key.

Adding a device

A new device can reach your folder, but it can’t read it without the key. Adding a device is how it gets the key.

One device shows a one-time code. Sval puts the key in the folder, locked with that code. You type the code on the other device, and Sval there unlocks the key and starts syncing. The locked key then leaves the folder.

That’s why both devices need the same folder before you start, and why the code can take a few minutes to arrive: it travels the way your Workspaces do. The code works for an hour. Anyone with both the code and your folder could read your Workspaces, so keep the code to yourself.

What syncs

Sval syncs your tabs, Workspaces, groups, Favorites, history, and settings, including your choices for each site and your blocking setup.

Some things stay on each device:

Your sign-ins and cookies. You sign in to sites once on each device.
Which folder the device syncs through, and the device’s name.
Your password manager’s extension, which each device installs.
Whether AI assistants can use Sval on that device.
Which side of the window the panel is on.
Tabs in private windows, which are never saved or synced.

Shutting out a device

A device that has your key can read your folder for as long as the key stays the same. To shut a lost device out, set up sync again with a new key. Your other devices then need a new code each, and the old key reads nothing. See Set up sync again with a new key.