Mr Merchant: Medium’s word processor is totally unsuited to poetry, especially as it won’t allow floating lines. But I have never had trouble with breaks between stanza. I write into a text editor then paste the final poem into a word processor (in my case, LibreOffice Writer) as simple text. Then I paste the poem onto Medium. again as simple text. The stanza breaks stay. You might try writing and pasting directly from a text editor. I don’t know. Maybe someone else reading this can help. Sorry.