Steps to Reproduce

1. Open a Keikai book
2. Edit cell A1 with some content
3. Copy the content of cell A1
4. Paste to cell B2
5. Attempt to clone the book using book.cloneBook()

Current Result

The book.cloneBook() operation fails with the following error:

java.lang.InternalError: java.io.NotSerializableException: io.keikai.api.impl.RangeImpl$SharedContext

Expected Result

The book.cloneBook() operation should successfully create a clone of the book.