The idea is not to sacrifice selfrando (or whatever similar means come to mind) for sandboxing. Sandboxed Tor Browser is pretty much agnostic to whatever Tor Browser version it is used with (it lets you select on which channel you want to be at start-up). All in all we still think that the current sandboxing code for Linux makes it less likely that a user gets exploited compared to using the hardened version. Sure, we can make the result even better by shipping selfrando to alpha (and later stable) users and that is planned and currently worked on.
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