Add backend to access Nextcloud Notes

I found an article from March 2017 stating that Nextcloud Notes should automatically be accessible in Evolution via GOA, but that obviously is not the case (any more?).

Notes are not listed in the selectable features of a GOA Nextcould account, the GOA Nextcloud account does not show up in the Evolution Notes tab, and it's also not possible to add Nextcloud Notes via CalDAV (when trying to add a CalDAV account and clicking on the button "Search Notes Lists" no results are shown for the chosen Nextcloud account).

I assume something has changed since then, the Evolution Notes tab mentions "Notes Lists" but Nextcloud Notes works with single .txt files (one file per note) in the Notes folder.

So what happened and is there a solution?

I know that I can just access the files in the Notes folder using Nautilus, but it would be a pity to miss out on the integration in Evolution to have it all in one place.