Seen this UA turn up today:

Nextcloud Server Crawler

Made a pair of requests to my landing page. No request for robots. No referrer. Request headers were empty, except for "gzip". Hit was from 70.249.170.193 (part of an AT&T bulk /15 assignment). No host name.

Looked through 5+ years of logs, have seen it only twice before - July 10 / 2021 and August 14 / 2023 (both were Comcast IP's). Same MO as today.

Since blocking it by IP is likely impossible, my webserver will now give a standard "I think you're a bot" page when it sees "Nextcloud" in the UA.