Mozilla released the next scheduled update for the Thunderbird 38.x branch with 38.2.0 on August 14, 2015. There have been some changes to this version for increased stability.
- CHANGED: Hardware acceleration is now disabled by default to avoid crashing Thunderbird
- FIXED: A few bugs have been fixed to avoid crashing Thunderbird
- UNRESOLVED: The “maildir” storage type can no longer be set through the UI due to various issues. Power users can still set the storage type using the config editor.
The next planned update for the Thunderbird 38.x branch will be around September 22nd with Thunderbird 38.3.0 release. Users can update from within Thunderbird via Help > About Thunderbird and following the prompts. User may also manually download and install the update from the getthunderbird.com site.