Alert TorBirdy devs about Thunderbird upstream patch prefs
Originally created by @Anonymous on #11481 (Redmine)
When the Icedove patches land upstream we should alert TorBirdy devs about :
- mailnews.auto_config.ssl_only which is set by default in Icedove and
- the need to se mailnews.auto_config.dns_mx_lookup.enabled to False in Torbirdy.
The latter is done in Tails already.