GPG signatures for TorBirdy releases are available at dist.torproject.org.
TorBirdy changes many Thunderbird settings that it enforces; the Before using TorBirdy section on the website explains this in detail. The preference changes are documented on the wiki.
To report bugs, please use the bug tracker and not the reviews section.
NOTE: This add-on disables the Google Safe Browsing and Microsoft Family Safety for privacy reasons. If you are interested to know why, please see 1, 2 (Tor Project bug tracker links) for more information.
This is an experimental add-on and it requires that a user has Tor installed.
We are still in beta so the usual caveats apply.