New features may be incomplete works in progress, because some are completed and polished over a period of weeks. The <a href="https://thunderbird.topicbox.com/groups/beta">beta forum</a> may provide more information on feature progress.
新功能可能并未开发完毕，有些功能需要用几周时间来完善。<a href="https://thunderbird.topicbox.com/groups/beta">测试版论坛</a>可能会提供开发的最新进展。