- Thunderbird 17.0.2esr
- Thunderbird 17.0.2#
Week of January 13th
- Thunderbird 19 Beta (19.0b1)
- Thunderbird 20 Earlybird (20.0a2)
- Thunderbird 17.0.3#
- Thunderbird 17.0.3esr
- Thunderbird 20 Beta (20.0b1)*
- Thunderbird 21 Earlybird (21.0a2)*
- Thunderbird 17.0.4
- Thunderbird 17.0.4esr
- Thunderbird 21 Beta (20.0b1)*
- Thunderbird 22 Earlybird (21.0a2)*
# Do to the shift in Thunderbird development strategy, build numbering for releases will now be based of the current ESR branch numbering.
* As part of the new Rapid Release Schedule, dates listed for Earlybird and Beta builds reflect when the code merge is set to begin. The actual release to that particular channel may vary by several days.