title: What happens to queued messages when Logback's AsyncAppender crashes?
body: <p>When using Logback's <code>AsyncAppender</code>, messages get queued before they
  are written to their final destination (depending on which <code>Appender</code>
  you wrapped with the <code>AsyncAppender</code>).  So far so good. </p>
  
  <p>Is it possible those queued messages get lost when my program or logback itself crash?</p>