Provide "New Identity" option that uses session restore
People routinely request a New Identity option that doesn't close all of their tabs. Unfortunately, this is not really possible to implement while still clearing all of the tracking-related browser state.
However, what we can do is store a memory-only instance of the session restore data prior to New Identity and then restore it afterwords. This might be rather klunky in terms of responsiveness and load delay, but it would give people who really don't want to lose their current tabs a way to still keep them without quite so much tracking data persisting across the "New Identity" invocation.