Virtual Machine Isolated Tabs

[S_A_C_]

I propose a new isolated Firefox window that launches an ephemeral, immutable QEMU‑based Linux VM running only Firefox. This would allow untrusted websites to be used with greatly reduced risk, though VM escapes and network tunnel risks remain and must be mitigated. Users should be warned not to enter personal data, as the VM itself can still be temporarily compromised, and also that isolation is not perfect and only protects the host from the VM but not the VM from a compromised host.

The VM would run as a separate user with no host Firefox data. For security, GPU acceleration + clipboard should be disabled, the VM and OS must be properly configured, and Wayland + Firejail (with network namespaces and NAT obfuscation) should be used for privacy and to reduce attack surface. Downloads could be limited to safe file types (MP4, JPG, TXT, etc.), require host confirmation, and be sanitized before moving to the host download folder. VM settings could be configurable in the hosts Firefox settings page.

Although complex and adding bulk, this feature could be optional and would significantly enhance secure browsing.

Thank you!

[Jon]

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