Doesn't seem to work as a WebDAV server. edit: I wanted to let Zotero sync to my phone, which didn't work (with and without the URL path prefix). I'm using the WebDAV FS app now, which works.
Developer reply
I see. Zotero's authentication flow triggers a bug, this will be fixed in the next version. For now it only works without login. For HTTPS you will also need to set up certificate override in Zotero, they have instructions on their website.