tor stalls at 25% bootstrapped unless there is a fingerprint in the Bridge line
According to the tor man page, the Bridge
option of the client's torrc file does not require a fingerprint:
If "fingerprint" is provided (using the same format as for
DirAuthority), we will verify that the relay running at that
location has the right fingerprint.
However, ever since the fixes for #40106 (closed) (I did a git bisect, but couldn't narrow down exactly which commit was the culprit due to other transport related bugs), my bootstrap stalls at 25% unless a fingerprint is provided (with an empty datadir it stalls at 70% weirdly). I have tested this with both Snowflake and Obfs4.
If there's a good security reason to require the fingerprint, we should update the manpage, and also make sure that we always distribute the fingerprint with bridge lines. I'd prefer not requiring the fingerprint since some transports like snowflake have the proxies, not the client, decide which bridge to connect to.