Question: content.files_optional + sign

Has there been a change in siteSign and files_optional object?

Before: sign failed for missing optional files in user directory. As a workaround I always clear files_optional object before sign. The optional files in user directory were added to files_optional object. OK functionality.
Now: clear files_optional object before sign => all optional files are deleted from user directory. Is that an error or is it how it should be?