When a receiving transaction is committed in a paging situation,
if a page happens to be completed and it will be deleted in a
transaction operation (PageCursorTx). The other tx operation
RefsOperation needs to access the page (in PageCache) to finish
its job. There is a chance that the PageCursorTx removes the
page before RefsOperation and it will cause the RefsOperation
failed to find a message in a page.