v0.9.5

• Compiling no longer reads the model while an edit is changing it. A compilation started from
  the editor walked and copied the open document's model on its own thread with no lock, while
  typing could reparse that same model underneath it. Copying also resolves references, which
  writes to the model, so the two threads could corrupt its internal bookkeeping. That is one way
  to end up with errors like NullPointerException ... "adapter" is null and an empty preview. The
  compilation now takes its copy as a proper read of the document, waiting for any edit in
  progress, and uses the model as it stands after that edit rather than the one it was asked
  about.