Weired encryption

Running 1.0.179 on desktop and notebook, each on Ubuntu (one bionic, one eoan).
Backend is nextcould, using webdav.

Notebook is syncing fine to nextcould, encryption is enabled, notes on nextcould look encrypted to me (e.g. encryption_applied: 1, encryption_cipher_text is unreadable, cipher is aes,…).
Now adding the desktop (after deleting .config/Joplin and .config/joplin-desktop, I’m not trying for the first time…).
Desktop creates some welcome-notes, which I delete before configuring synchronization. Those are uploaded unencrpted. Nextcloud now contains some notes in clear and some encrypted. Desktop tells me: “Encryption is Disabled, Decrypted items: 14/383”. I have the option to enable encryption.
Notebook tells me: “Encryption is Enabled, decrypted items: 401/401”. I have the option to disable encryption.
Neither desktop nor notebook show a list of encryption keys.

In the past, with a different provider, I had no issues. Now I’m confused. Any ideas?