[Feature request] proxy/VPN that is only applied to a container (not system-wide)

[fallenguru]

AFAICT the current incarnation of Mozilla VPN operates system-wide, i.e. it affects all traffic, not just the browser. While I can see why someone might want this, I'd much prefer a solution that only applies to the browser, and then only to a specific container [window/tab/site, really, but the Container extension already handles that]. More specifically, the VPN profile should be per container.

Ideally, no external helper application would be required, i.e. implementation within an add-on.

Rationale: A system-wide VPN is rather invasive re. the system configuration and at the same time very coarse, split tunnelling or no, if what you want is spoof your geolocation to three countries in as many tabs and be as anonymous as possible (multi-hop, random exit) in tab four and five ... but not run, say, your system updates over a VPN.

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