Multi-Session Browsers
Symphony Browser
A Chromium browser where every tab runs as its own isolated session, with advanced fingerprint blocking.
- Chromium
- C++
- Session isolation
- Fingerprint protection
What was built
Symphony changes how a browser treats sessions. Instead of sharing one profile across all tabs, each tab runs as its own isolated session, with its own cookies, storage and cache, so activity in one tab cannot see or reach another. Fingerprint blocking is built directly into the browser rather than added as an extension, covering the signals sites use to tell devices apart. The result is a browser built for holding many separate sessions open side by side in a single window.
The engineering challenge
In stock Chromium, cookies, storage and cache are shared across tabs in a profile. Giving every tab its own session means changing how storage and browsing contexts are created and cleaned up, not just adding a new interface on top. Combining that with fingerprint blocking raises the bar further: each isolated session needs its own consistent canvas, WebGL, audio and font signals, not just separate storage.
How it works
Illustration: a shared browser profile compared with per-tab sessions.
Engineering scope and what shipped
- Multi-session architecture with each tab isolated from the others
- Advanced fingerprint blocking
Related services
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