If 2.57a1 then no Bookmark Manager, no mail, no news, no sidebar and no help
currently too. Stick with 2.49.x for now.
If you need it the candidate is probably the final:
It just needs to be verified and move to release. There is a 0.01% chance that
one of the final steps fails in such a way that a new build is needed but even
then it would be working fine until a build 2 is finished.
If urgent go to Nightly. Last is 2.57a1
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