Had never heard of this before today. Anyone tried it?

EDIT: "Being a fork of Mozilla Thunderbird, the software collects some data about the user, less than the original Mozilla Thunderbird, as outlined in Thunderbird's privacy statement. No data is submitted to Betterbird, some data may be submitted to Mozilla. No telemetry and no crash reports are submitted, however, add-on updates and blocklists are downloaded from Mozilla sites. Betterbird offers a product Start Page which processes access data as described above."