[*WebTunnel*](https://blog.torproject.org/introducing-webtunnel-evading-censorship-by-hiding-in-plain-sight/)is a bridge technology that is particularly good at circumventing censorship and might work from places where *obfs4* bridges are blocked. *WebTunnel* disguises your connection as ordinary web traffic.
If you cannot do an automatic upgrade or if Tails fails to start after an automatic upgrade, please try to do a [[manual upgrade|doc/upgrade/#manual]].