The version 5.6.4 is available for download.
This release correct an inconsistency in the Notebook. There, when selecting «Cancel» after having made any changes, and re-invoke the Notebook, it appeared as if the changes were maintained, but actually that appearance was maintained only during the current session. When closing the application and re-enter, we can see that the changes had not been retained. The modification makes the behavior more into line with user expectations. Now, after some changes if you select «Cancel» and then comeback to the Notebook in the same working session, it is found that recent changes have not been preserved.